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POApp using camera flash as a torch using Eclipse not working
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copied!<p>I have been working on an app to use a phone's/tablet's camera flash as a flashlight. Everything seemed to be working fine but when I tested it on my Droid Bionic running Android 4.1.2, the app failed to turn on the flash even though it said it did. Here is the java code I used:</p> <pre><code> package com.example.flash; import android.app.Activity; import android.content.Context; import android.content.Intent; import android.content.pm.PackageManager; import android.hardware.Camera; import android.hardware.Camera.Parameters; import android.os.Bundle; import android.util.Log; import android.view.Menu; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.Toast; public class MainActivity extends Activity { private boolean isFlashOn = false; private Camera camera; private Button button; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); button = (Button) findViewById(R.id.buttonFlashlight); Context context = this; PackageManager pm = context.getPackageManager(); if(!pm.hasSystemFeature(PackageManager.FEATURE_CAMERA)) { Log.e("err", "Device has no camera!"); Toast.makeText(getApplicationContext(), "Your device doesn't have camera!",Toast.LENGTH_SHORT).show(); return; } camera = Camera.open(); final Parameters p = camera.getParameters(); button.setOnClickListener(new OnClickListener() { public void onClick(View arg0) { if (isFlashOn) { Log.i("info", "torch is turned off!"); p.setFlashMode(Parameters.FLASH_MODE_OFF); camera.setParameters(p); isFlashOn = false; button.setText("Tap to turn flashlight on."); } else { Log.i("info", "torch is turned on!"); p.setFlashMode(Parameters.FLASH_MODE_TORCH); camera.setParameters(p); isFlashOn = true; button.setText("Tap to turn flashlight off."); } } }); } @Override public boolean onCreateOptionsMenu(Menu menu) { // Inflate the menu; this adds items to the action bar if it is present. getMenuInflater().inflate(R.menu.main, menu); return true; } @Override protected void onStop() { super.onStop(); if (camera != null) { camera.release(); } }} </code></pre> <p>Is this code correct or did I miss something?</p> <p>Logcat:</p> <pre><code>07-03 18:48:29.064: E/Trace(773): error opening trace file: No such file or directory (2) 07-03 18:48:30.535: D/Camera(773): app passed NULL surface 07-03 18:48:31.023: D/libEGL(773): loaded /system/lib/egl/libEGL_emulation.so 07-03 18:48:31.073: D/(773): HostConnection::get() New Host Connection established 0x2a13c3c0, tid 773 07-03 18:48:31.123: D/libEGL(773): loaded /system/lib/egl/libGLESv1_CM_emulation.so 07-03 18:48:31.173: D/libEGL(773): loaded /system/lib/egl/libGLESv2_emulation.so 07-03 18:48:31.406: W/EGL_emulation(773): eglSurfaceAttrib not implemented 07-03 18:48:31.433: D/OpenGLRenderer(773): Enabling debug mode 0 07-03 18:48:31.723: I/Choreographer(773): Skipped 58 frames! The application may be doing too much work on its main thread. 07-03 18:49:05.923: D/dalvikvm(773): GC_CONCURRENT freed 202K, 12% free 2623K/2956K, paused 74ms+25ms, total 234ms 07-03 18:49:06.216: W/EGL_emulation(773): eglSurfaceAttrib not implemented 07-03 18:49:09.584: D/Camera(773): app passed NULL surface 07-03 18:49:09.853: W/EGL_emulation(773): eglSurfaceAttrib not implemented 07-03 18:49:11.813: I/info(773): torch is turned on! 07-03 18:49:13.467: I/info(773): torch is turned off! 07-03 18:49:16.263: W/EGL_emulation(773): eglSurfaceAttrib not implemented 07-03 18:49:16.713: D/AndroidRuntime(773): Shutting down VM 07-03 18:49:16.713: W/dalvikvm(773): threadid=1: thread exiting with uncaught exception (group=0x40a71930) 07-03 18:49:16.936: E/AndroidRuntime(773): FATAL EXCEPTION: main 07-03 18:49:16.936: E/AndroidRuntime(773): java.lang.RuntimeException: Method called after release() 07-03 18:49:16.936: E/AndroidRuntime(773): at android.hardware.Camera._stopPreview(Native Method) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.hardware.Camera.stopPreview(Camera.java:543) 07-03 18:49:16.936: E/AndroidRuntime(773): at com.example.flash.MainActivity.surfaceDestroyed(MainActivity.java:140) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.view.SurfaceView.updateWindow(SurfaceView.java:553) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.view.SurfaceView.onWindowVisibilityChanged(SurfaceView.java:231) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.view.View.dispatchWindowVisibilityChanged(View.java:7544) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.view.ViewGroup.dispatchWindowVisibilityChanged(ViewGroup.java:1039) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.view.ViewGroup.dispatchWindowVisibilityChanged(ViewGroup.java:1039) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.view.ViewGroup.dispatchWindowVisibilityChanged(ViewGroup.java:1039) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.view.ViewGroup.dispatchWindowVisibilityChanged(ViewGroup.java:1039) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1211) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:989) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:4351) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.view.Choreographer$CallbackRecord.run(Choreographer.java:749) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.view.Choreographer.doCallbacks(Choreographer.java:562) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.view.Choreographer.doFrame(Choreographer.java:532) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:735) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.os.Handler.handleCallback(Handler.java:725) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.os.Handler.dispatchMessage(Handler.java:92) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.os.Looper.loop(Looper.java:137) 07-03 18:49:16.936: E/AndroidRuntime(773): at android.app.ActivityThread.main(ActivityThread.java:5041) 07-03 18:49:16.936: E/AndroidRuntime(773): at java.lang.reflect.Method.invokeNative(Native Method) 07-03 18:49:16.936: E/AndroidRuntime(773): at java.lang.reflect.Method.invoke(Method.java:511) 07-03 18:49:16.936: E/AndroidRuntime(773): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793) 07-03 18:49:16.936: E/AndroidRuntime(773): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560) 07-03 18:49:16.936: E/AndroidRuntime(773): at dalvik.system.NativeStart.main(Native Method) 07-03 18:49:24.854: E/Trace(811): error opening trace file: No such file or directory (2) 07-03 18:49:25.413: D/libEGL(811): loaded /system/lib/egl/libEGL_emulation.so 07-03 18:49:25.567: D/(811): HostConnection::get() New Host Connection established 0x2a15f570, tid 811 07-03 18:49:25.643: D/libEGL(811): loaded /system/lib/egl/libGLESv1_CM_emulation.so 07-03 18:49:25.663: D/libEGL(811): loaded /system/lib/egl/libGLESv2_emulation.so 07-03 18:49:25.934: W/EGL_emulation(811): eglSurfaceAttrib not implemented 07-03 18:49:25.963: D/OpenGLRenderer(811): Enabling debug mode 0 07-03 18:53:12.298: D/Camera(811): app passed NULL surface 07-03 18:53:12.723: D/dalvikvm(811): GC_CONCURRENT freed 172K, 11% free 2600K/2904K, paused 9ms+165ms, total 421ms 07-03 18:53:12.934: E/EGL_emulation(811): rcCreateWindowSurface returned 0 07-03 18:53:12.934: E/EGL_emulation(811): tid 811: eglCreateWindowSurface(631): error 0x3003 (EGL_BAD_ALLOC) 07-03 18:53:12.943: D/AndroidRuntime(811): Shutting down VM 07-03 18:53:12.943: W/dalvikvm(811): threadid=1: thread exiting with uncaught exception (group=0x40a71930) 07-03 18:53:13.033: E/AndroidRuntime(811): FATAL EXCEPTION: main 07-03 18:53:13.033: E/AndroidRuntime(811): java.lang.RuntimeException: createWindowSurface failed EGL_BAD_ALLOC 07-03 18:53:13.033: E/AndroidRuntime(811): at android.view.HardwareRenderer$GlRenderer.createSurface(HardwareRenderer.java:1064) 07-03 18:53:13.033: E/AndroidRuntime(811): at android.view.HardwareRenderer$GlRenderer.createEglSurface(HardwareRenderer.java:961) 07-03 18:53:13.033: E/AndroidRuntime(811): at android.view.HardwareRenderer$GlRenderer.initialize(HardwareRenderer.java:787) 07-03 18:53:13.033: E/AndroidRuntime(811): at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1502) 07-03 18:53:13.033: E/AndroidRuntime(811): at android.view.ViewRootImpl.doTraversal(ViewRootImpl.java:989) 07-03 18:53:13.033: E/AndroidRuntime(811): at android.view.ViewRootImpl$TraversalRunnable.run(ViewRootImpl.java:4351) 07-03 18:53:13.033: E/AndroidRuntime(811): at android.view.Choreographer$CallbackRecord.run(Choreographer.java:749) 07-03 18:53:13.033: E/AndroidRuntime(811): at android.view.Choreographer.doCallbacks(Choreographer.java:562) 07-03 18:53:13.033: E/AndroidRuntime(811): at android.view.Choreographer.doFrame(Choreographer.java:532) 07-03 18:53:13.033: E/AndroidRuntime(811): at android.view.Choreographer$FrameDisplayEventReceiver.run(Choreographer.java:735) 07-03 18:53:13.033: E/AndroidRuntime(811): at android.os.Handler.handleCallback(Handler.java:725) 07-03 18:53:13.033: E/AndroidRuntime(811): at android.os.Handler.dispatchMessage(Handler.java:92) 07-03 18:53:13.033: E/AndroidRuntime(811): at android.os.Looper.loop(Looper.java:137) 07-03 18:53:13.033: E/AndroidRuntime(811): at android.app.ActivityThread.main(ActivityThread.java:5041) 07-03 18:53:13.033: E/AndroidRuntime(811): at java.lang.reflect.Method.invokeNative(Native Method) 07-03 18:53:13.033: E/AndroidRuntime(811): at java.lang.reflect.Method.invoke(Method.java:511) 07-03 18:53:13.033: E/AndroidRuntime(811): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793) 07-03 18:53:13.033: E/AndroidRuntime(811): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560) 07-03 18:53:13.033: E/AndroidRuntime(811): at dalvik.system.NativeStart.main(Native Method) </code></pre>

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