1page.title=Troubleshooting 2parent.title=FAQs, Tips, and How-to 3parent.link=index.html 4@jd:body 5 6 7<p>Here are some tips and tricks for common Android errors. Don't forget to use the 8 ddms logcat capability to get a deeper view when errors occur. 9 See the <a href="{@docRoot}guide/developing/debugging/index.html">Debugging</a> documentation for more information.</p> 10<ul> 11 <li><a href="#installeclipsecomponents">ADT Installation Error: "requires plug-in org.eclipse.wst.sse.ui".</a></li> 12 <li><a href="#nodevice">ADB reports "no device" when an emulator is running</a></li> 13 <li><a href="#noapp">My new application/activity isn't showing up in the device application 14 list </a></li> 15 <li><a href="#noupdate">I updated my app, but the updates don't seem to be showing up on 16 the device</a></li> 17 <li><a href="#layout_wilih">I'm getting a "Binary XML file line #2: You must supply a layout_wilih 18 attribute" error when I start an application</a></li> 19 <li><a href="#permission">My request to (<em>make a call, catch an incoming SMS, receive 20 a notification, send an intent to an Android application</em>) is being 21 ignored</a></li> 22 <li><a href="#build">Help! My project won't build in Eclipse</a></li> 23 <li><a href="#eclipse">Eclipse isn't talking to the emulator</a></li> 24 <li><a href="#majorminor">When I go to preferences in Eclipse and select "Android", I get the following error message: Unsupported major.minor version 49.0.</a></li> 25 <li><a href="#apidemosreinstall">I can't install ApiDemos apps in my IDE because of a signing error</a></li> 26 <li><a href="#gesturebuilderinstall">I can't install the GestureBuilder sample 27app in the emulator</a></li> 28 <li><a href="#signingcalendar">I can't compile my app because the build tools generated an expired debug certificate</a></li> 29 <li><a href="#manifestfiles">Unable to view manifest files from within Eclipse</a></li> 30</ul> 31 32<a name="installeclipsecomponents" id="installeclipsecomponents"></a><h2>ADT Installation Error: "requires plug-in org.eclipse.wst.sse.ui".</h2> 33<p> 34The "Android Editors" feature of the ADT Plugin requires specific Eclipse components, such as WST. If you 35encounter this error message during ADT installation, you need to install the 36required Eclipse components and then try the ADT installation again. Follow the steps below to install the required components for the 37Android Editors feature, based on the version of Eclipse that you are using.</p> 38 39<table style="font-size:100%"> 40<tr><th>Eclipse 3.3 (Europa)</th><th>Eclipse 3.4 (Ganymede)</th></tr> 41<tr> 42<td width="50%"> 43<ol> 44<li>From the dialog where you select the <strong>Update sites to visit</strong>, select the checkboxes for both the 45ADT site, and the Callisto/Europa/Ganymede Discovery Site (you may want to 46check <strong>Automatically select mirrors</strong> at the bottom).</li> 47<li>Click <strong>Finish</strong>.</li> 48<li>In the <strong>Next</strong> dialog, select the Android Plugins.</li> 49<li>Now, expand the tree item of the discovery site. It seems that if you 50don't do it, it doesn't load the content of the discovery site.</li> 51<li>On the right, click <strong>Select required</strong>. This will select all the components 52that are required to install the Android plugin (wst, emf, etc...).</li> 53<li>Click <strong>Next</strong>, accept the agreement, click <strong>Install All</strong>, and restart Eclipse.</li> 54</ol> 55</td> 56<td> 57<ol> 58 <li>Select <strong>Help</strong> > <strong>Software Updates...</strong></li> 59 <li>Select the <strong>Installed Software</strong> tab.</li> 60 <li>Click <strong>Update...</strong></li> 61 <li>If an update for ADT is available, select it and click <strong>Finish</strong>.</li> 62</ol> 63</td> 64</tr> 65</table> 66 67 68</p> 69<a name="nodevice"></a><h2>ADB reports "no device" when an emulator is running</h2> 70 <p>Try restarting adb by stopping it (<code>adb 71 kill-server</code>) then any other adb command to restart it.</p> 72 73<a name="noapp"></a><h2>My new application/activity isn't showing up in the 74 applications list </h2> 75<ul> 76 <li>You often must restart your device or emulator before a new activity shows 77 up in the applications list. This is particularly true when it is a completely 78 new application with a new AndroidManifest.xml file.</li> 79 <li>If this is for a new activity in an existing AndroidManifest.xml file, did 80 you include an <code><activity></code> tag for your app (or a <code><service></code> tag 81 for a service, or a <code><receiver></code> tag for a receiver, etc.)? </li> 82 <li>Make sure that your AndroidManifest.xml file is valid. Errors in attribute 83 values, such as the <em>value </em> attribute in <code><action <em>value</em>="<em><something></em>"></code> 84 will often not be caught by compilers, but will prevent your application 85 from being displayed because the intent filter will not be matched. Extra 86 spaces or other characters can often sneak into these strings.</li> 87 <li>Did you send your .apk file to the device (<a href="{@docRoot}guide/developing/tools/adb.html#move">adb install</a>)?</li> 88 <li>Run logcat on your device (<code>adb logcat</code>) 89 and then install your .apk file. Check the logcat output to see whether the 90 application is being installed and recognized properly. Here's sample output 91 from a successful installation: 92<pre>I/FileObserver( 414): *** onEvent wfd: 3 mask: 8 path: MyRSSReader.apk 93D/PackageManager( 414): Scanning package: /data/app/MyRSSReader.apk 94D/PackageManager( 414): Adding package com.example.codelab.rssexample 95D/PackageManager( 414): Registered content provider: my_rss_item, className = com.example.codelab.rssexample.RssContentProvider, isSyncable = false 96D/PackageManager( 414): Providers: com.example.codelab.rssexample.RssContentProvider 97D/PackageManager( 414): Activities: com.example.codelab.rssexample.MyRssReader com.example.codelab.rssexample.MyRssReader2 </pre> 98 </li> 99 <li>If logcat shows that the package manager is having problems loading the manifest 100 file, force your manifest to be recompiled by adding a space in the file and 101 compiling it.</li> 102</ul> 103<a name="noupdate"></a><h2>I updated my app, but the updates don't seem to be showing up on the device</h2> 104 <p>Did you remember to send your .apk file to the device (<a href="{@docRoot}guide/developing/tools/adb.html#move">adb 105 install</a>)?</p> 106 107<a name="layout_wilih"></a><h2>I'm getting a "Binary XML file line #2: You must supply a layout_wilih 108 attribute" error 109 when I start an application (but I declare a layout_wilih attribute <em>right 110 there!!!</em>)</h2> 111<ul> 112 <li>Make sure that the SDK you are building with is the same version as the Android 113 OS that you are running on. </li> 114 <li>Make sure that you're calling setContentView() early in your onCreate() method. 115 Calling other methods, such as setListAdapter() before calling setContentView() 116 can sometimes create odd errors when Android tries to access screen elements 117 that haven't been set before.</li> 118</ul> 119<a name="permission"></a><h2>My request to (<em>make a call, catch an incoming SMS, 120receive a notification, send an intent to an Android application</em>) is being 121ignored</h2> 122 <p>You might not have permission (or might not have requested permission) to 123 call this activity or receive this intent. Many standard Android activities, 124 such as making a call, have a permission assigned to it to prevent arbitrary 125 applications from sending or receiving requests. See <a 126 href="{@docRoot}guide/topics/security/security.html">Security and 127 Permissions</a> for more information on permissions, and 128 {@link android.Manifest.permission Manifest.permission} for a list of 129 standard permissions supported by the Android platform. 130</p> 131<a name="build"></a><h2>Help! My project won't build in Eclipse</h2> 132<p>If your project doesn't build, you may notice symptoms such as new 133resources added in the <code>res/</code> sub-folders not showing up in the R class, 134the emulator not being started, not being able to run the application, or even seeming to run an old version of the application.</p> 135<p>To troubleshoot these types of problems, first try:</p> 136<ol> 137 <li>Switch to the DDMS view in Eclipse (if you don't already have it open): 138 <ol type="a"> 139 <li>From the menu select <code>Window > Open Perspective > Other</code></li> 140 <li>Select DDMS from the list and hit OK</li> 141 </ol> 142 </li> 143 <li>In the Devices panel (top right panel by default), click on the down triangle 144 to bring up the panel menu</li> 145 <li>Select <code>Reset ADB</code> from the menu, and then try running the 146 application again</li> 147</ol> 148<p>If the above still doesn't work, you can try these steps:</p> 149<ol> 150 <li> 151 Check the console and problems tabs at the bottom of the Eclipse UI 152 </li> 153 <li> 154 If there are problems listed in either place, they should give you a clue 155 what is wrong 156 </li> 157 <li> 158 If you aren't sure if the problems are fresh or stale, clear the console 159 with a right click > Clear, then clean the project 160 </li> 161 <li> 162 To clean the project (a good idea with any kind of build error), select 163 Project > Clean from the eclipse main menu, then select the project you 164 are working on (or clean all) 165 </li> 166</ol> 167<a name="eclipse"></a><h2>Eclipse isn't talking to the emulator</h2> 168<p>When communication doesn't seem to be happening between Eclipse and the emulator, symptoms can include: nothing happening when you press run, the emulator hanging waiting 169for a debugger to connect, or errors that Eclipse reports about not being able 170to find the emulator or shell. By far the most common symptom is that when you press run, the emulator starts (or 171is already running), but the application doesn't start.</p> 172<p> 173You may find any of these steps will fix the problem and with practice you 174probably can figure out which one you need to do for your particular issue, but 175to start with, the safest option is to run through all of them in order:</p> 176<ol> 177 <li> 178 Quit the emulator if it is running 179 </li> 180 <li> 181 Check that any emulator processes are killed (sometimes they can hang, use ps on unix or mac, or task manager in the process view on 182 windows). 183 </li> 184 <li> 185 Quit Eclipse 186 </li> 187 <li> 188 From the command line, type: 189<pre>adb kill-server </pre> 190 </li> 191 <li> 192 Start Eclipse and try again 193 </li> 194</ol> 195 196<a name="majorminor"></a><h2>When I go to preferences in Eclipse and select "Android", I get the following error message: Unsupported major.minor version 49.0.</h2> 197<p>This error is displayed if you are using an older version of the JDK. Please make sure you are using JDK version 5 or 6.</p> 198 199<h2 id="apidemosreinstall">I can't install ApiDemos apps in my IDE because of a signing error</a></h2> 200 201<p>The Android system requires that all applications be signed, as described in 202 <a href="{@docRoot}guide/publishing/app-signing.html">Signing Your Applications</a>. The ApiDemos 203applications included with the SDK are preinstalled on the emulator and for that reason have been 204compiled and signed with a private key.</p> 205 206If you want to modify or run one of the ApiDemos apps from Eclipse/ADT or other IDE, you can do so 207so only after you uninstall the <em>preinstalled</em> version of the app from the emulator. If 208you try to run an ApiDemos apps from your IDE without removing the preinstalled version first, 209you will get errors similar to: </p> 210 211<pre>[2008-08-13 15:14:15 - ApiDemos] Re-installation failed due to different application signatures. 212[2008-08-13 15:14:15 - ApiDemos] You must perform a full uninstall of the application. WARNING: ...This will remove the application data! 213[2008-08-13 15:14:15 - ApiDemos] Please execute 'adb uninstall com.android.samples' in a shell.</pre> 214 215<p>The error occurs because, in this case, you are attempting to install another copy of ApiDemos 216onto the emulator, a copy that is signed with a different certificate (the Android IDE tools will 217have signed the app with a debug certificate, where the existing version was already signed with 218a private certificate). The system does not allow this type of reinstallation. </p> 219 220<p>To resolve the issue, you need to fully uninstall the preinstalled and then reinstall it using 221the adb tool. Here's how to do that:</p> 222 223<ol> 224 <li>In a terminal, change to the tools directory of the SDK.</li> 225 <li>If no emulator instance is running, start an emulator using using the command <code>emulator</code>.</li> 226 <li>Uninstall the preinstalled app using the command <code>adb uninstall com.example.android.apis</code>.</li> 227 <li>Reinstall the app using the command <code>adb install <path to the ApiDemos.apk></code>. If you are 228 working in Eclipse/ADT, you can just compile and run the app in the normal way. </li> 229</ol> 230 231<p>Note that if multiple emulator instances are running, you need to direct your uninstall/install 232commands to the emulator instance that you are targeting. To do that you can add the 233<code>-s <serialNumber></code> to the command, for example: </p> 234 235<pre>adb -s emulator-5556 install</pre> 236 237<p>For more information about adb, see the <a href="{@docRoot}guide/developing/tools/adb.html">Android Debug Bridge</a> 238documentation.</p> 239 240<h2 id="gesturebuilderinstall">I can't install the GestureBuilder sample 241app in the emulator</a></h2> 242 243<p>This is similar to the ApiDemos problem described above, except that 244you cannot fix it by uninstalling GestureBuilder from the emulator. The 245GestureBuilder app cannot be uninstalled because it is currently installed 246within the system files themselves.</p> 247 248<p><strong>Symptoms</strong></p> 249 250<ul><li><p>You cannot run GestureBuilder in the emulator:</p> 251 252<pre>[2009-12-10 14:57:19 - GestureBuilderActivity]Re-installation failed due to different application signatures. 253[2009-12-10 14:57:19 - GestureBuilderActivity]You must perform a full uninstall of the application. WARNING: This will remove the application data! 254[2009-12-10 14:57:19 - GestureBuilderActivity]Please execute 'adb uninstall com.android.gesture.builder' in a shell.</pre> 255</li> 256 257<li><p>Running <code>adb uninstall com.android.gesture.builder</code> fails:</p> 258<pre>$ adb uninstall com.android.gesture.builder 259 Failure</pre> 260</li></ul> 261 262<p>For now, the work-around is to change the sample's package name 263so that the system can install it as a new app rather than as a 264replacement for the existing GestureBuilder app. To change the 265package name, open the manifest file and modify the package attribute 266of the manifest element. Next, update imports and other references to 267the package name, rebuild the app, and run it in an AVD.</p> 268 269<p>For example, here's how you could do this in Eclipse:</p> 270 271<ol> 272 <li>Right-click on the package name 273(<code>src/com.android.gesture.builder</code>).</li> 274 <li>Select <strong>Refactor > Rename</strong> and change the name, for example to 275<code>com.android.gestureNEW.builder</code>. </li> 276 <li>Open the manifest file. Inside the <code><manifest></code> 277tag, change the package name to 278<code>com.android.gestureNEW.builder</code>.</li> 279 <li>Open each of the two Activity files and do Ctrl-Shift-O to add 280missing import packages, then save each file.</li> 281<li>Run the GestureBuilder application on the emulator.</li> 282</ol> 283 284<p>If you get an error message such as "Could not load /sdcard/gestures. 285Make sure you have a mounted SD card," be sure that your target AVD has an 286SD card. To create an AVD that has an SD card, specify one when creating 287an AVD with the AVD manager. See 288<a href="{@docRoot}guide/developing/devices/managing-avds.html#createavd"> 289Creating and Managing AVDs with AVD Manager</a> for more information.</p> 290 291<h2 id="signingcalendar">I can't compile my app because the build tools generated an expired debug certificate</h2> 292 293<p>If your development machine uses a locale that has a non-Gregorian calendar, you may encounter problems when first trying to compile and run your application. Specifically, you may find that the Android build tools won't compile your application because the debug key is expired. </p> 294 295<p>The problem occurs because the Keytool utility — included in the JDK and used by the Android build tools — fails to properly handle non-Gregorian locales and may create validity dates that are in the past. That is, it may generate a debug key that is already expired, which results in the compile error.</p> 296 297<p>If you encounter this problem, follow these steps to work around it: </p> 298 299<ol> 300<li>First, delete the debug keystore/key already generated by the Android build tools. Specifically, delete the <code>debug.keystore</code> file. On Linux/Mac OSX, the file is stored in <code>~/.android</code>. On Windows XP, the file is stored in <code> 301C:\Documents and Settings\<user>\.android</code>. On Windows Vista, the file is stored in <code> 302C:\Users\<user>\.android</code></li> 303<li>Next, you can either 304<ul> 305<li>Temporarily change your development machine's locale (date and time) to one that uses a Gregorian calendar, for example, United States. Once the locale is changed, use the Android build tools to compile and install your app. The build tools will regenerate a new keystore and debug key with valid dates. Once the new debug key is generated, you can reset your development machine to the original locale. </li> 306<li>Alternatively, if you do not want to change your machine's locale settings, you can generate the keystore/key on any machine using the Gregorian calendar, then copy the <code>debug.keystore</code> file from that computer to the proper location on your development machine. </li> 307</ul> 308</li> 309</ol> 310 311<p>This problem has been verified on Windows and may apply to other platforms. </p> 312 313<p>For general information about signing Android applications, see 314<a href="{@docRoot}guide/publishing/app-signing.html">Signing Your Applications</a>. </p> 315 316<h2 id="manifestfiles">Unable to view manifest files from within 317Eclipse</a></h2> 318 319<p>When you try to open an application's manifest file from within 320Eclipse, you might get an error such as this one:</p> 321<pre>An error has occurred. See error log for more details. 322org.eclipse.wst.sse.ui.StructuredTextEditor.isBlockSelectionModeEnabled()Z</pre> 323 324<p>Try reverting to the 3.0 version of the Eclipse XML Editors and 325Tools. If this does not work, remove the 3.1 version of the tool. To do 326this in Eclipse 3.4:</p> 327 328<ol> 329 <li>Select <strong>Help > Software Updates...</strong></li> 330 <li>Select the <strong>Installed Software</strong> tab.</li> 331 <li>Select <strong>Eclipse XML Editors and Tools</strong>.</li> 332 <li>Click <strong>Uninstall</strong>.</li> 333 <li>Click <strong>Finish</strong>.</li> 334</ol> 335 336<p>When you restart Eclipse, you should be able to view the manifest 337files. </p>