【发布时间】：2015-06-17 11:28:27
【问题描述】：
在我的应用程序中，我创建了一个自定义相机应用程序，在 Xml 中使用 FrameLayout。我有一个捕获按钮来捕获图像，还有另外两个按钮。这些按钮排列在RelativeLayout 内FrameLayout 内。但是运行我的应用程序时它不显示。这个问题的任何解决方案。有人可以帮忙吗？
XML 文件
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent"
>
<FrameLayout
android:id="@+id/camera_preview"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="1">
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
>
<ImageButton
android:id="@+id/buttonLoadPicture2"
android:layout_width="90dp"
android:layout_height="90dp"
android:layout_marginBottom="5dp"
android:layout_marginLeft="10dp"
android:layout_marginRight="5dp"
android:layout_marginTop="0dp"
android:layout_weight="1"
android:adjustViewBounds="true"
android:padding="6dp"
android:scaleType="fitCenter"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"/>
<ImageButton
android:id="@+id/button_capture"
android:layout_width="90dip"
android:layout_height="50dip"
android:layout_marginBottom="5dp"
android:layout_marginLeft="10dp"
android:layout_marginTop="0dp"
android:layout_toRightOf="@+id/buttonLoadPicture2"
android:layout_alignParentBottom="true"
android:src="@drawable/camera"
android:layout_marginRight="5dp"
/>
<Button android:id="@+id/buttonLoadPicture3"
android:layout_width="90dip"
android:layout_height="50dip"
android:layout_alignParentBottom="true"
android:layout_gravity="end"
android:layout_toRightOf="@+id/button_capture"
android:layout_marginBottom="5dp"
android:layout_marginLeft="10dp"
android:layout_marginRight="5dp"
android:layout_marginTop="0dp"
android:text="Cancel"
></Button>
</RelativeLayout>
</FrameLayout>
</LinearLayout>
JAVA 代码
public class CameraActivity extends Activity {
private Camera mCamera;
private CameraPreview mPreview;
public static final int MEDIA_TYPE_IMAGE = 1;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_camera);
ImageButton captureButton = (ImageButton) findViewById(R.id.button_capture);
System.out.println("Starting!");
// Create an instance of Camera
mCamera = getCameraInstance();
// Create our Preview view and set it as the content of our activity.
mPreview = new CameraPreview(this, mCamera);
FrameLayout preview = (FrameLayout) findViewById(R.id.camera_preview);
preview.addView(mPreview);
final Camera.PictureCallback mPicture = new Camera.PictureCallback() {
public void onPictureTaken(byte[] data, Camera camera) {
File pictureFile = getOutputMediaFile(MEDIA_TYPE_IMAGE);
if (pictureFile == null){
return;
}
try {
FileOutputStream fos = new FileOutputStream(pictureFile);
fos.write(data);
fos.close();
MediaStore.Images.Media.insertImage(getContentResolver(), pictureFile.getAbsolutePath(), pictureFile.getName(), pictureFile.getName());
} catch (FileNotFoundException e) {
} catch (IOException e) {
}
}
};
// Add a listener to the Capture button
captureButton.setOnClickListener(
new View.OnClickListener() {
public void onClick(View v) {
// get an image from the camera
System.out.println("Photo Taking!");
mCamera.takePicture(null, null, mPicture);
}
}
);
}
/** A safe way to get an instance of the Camera object. */
public static Camera getCameraInstance(){
Camera c = null;
try {
c = Camera.open(); // attempt to get a Camera instance
}
catch (Exception e){
// Camera is not available (in use or does not exist)
}
return c; // returns null if camera is unavailable
}
@Override
protected void onPause() {
super.onPause();
releaseCamera(); // release the camera immediately on pause event
}
private void releaseCamera(){
if (mCamera != null){
mCamera.release(); // release the camera for other applications
mCamera = null;
}
}
/** Create a File for saving an image or video */
private File getOutputMediaFile(int type){
// To be safe, you should check that the SDCard is mounted
// using Environment.getExternalStorageState() before doing this.
File mediaStorageDir = new File(Environment.getExternalStoragePublicDirectory(
Environment.DIRECTORY_PICTURES), "MyCameraApp");
// This location works best if you want the created images to be shared
// between applications and persist after your app has been uninstalled.
// Create the storage directory if it does not exist
if (! mediaStorageDir.exists()){
if (! mediaStorageDir.mkdirs()){
return null;
}
}
// Create a media file name
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
File mediaFile;
if (type == MEDIA_TYPE_IMAGE){
mediaFile = new File(mediaStorageDir.getPath() + File.separator +
"IMG_"+ timeStamp + ".jpg");
} else {
return null;
}
return mediaFile;
}
}
【问题讨论】：
-
可以提供java代码吗？因为它对我可见
-
你有
LinearLayout只有一个孩子：FrameKayout只有一个孩子：RelativeLayout，没有意义，去掉前两个 -
@Khushal Chouhan：请看我的编辑
-
您正在以编程方式将 CameraPreview 视图（无论是什么）添加到您的 FrameLayout。由于它是最后添加的，因此它将位于 FrameLayout 中的其他视图之上，这可能会掩盖其下方的视图。
标签： android android-layout android-camera android-xml