Java 当我将FrameLayout强制转换为ImageButton时,无法将其强制转换为FrameLayout
我有一个Java 当我将FrameLayout强制转换为ImageButton时,无法将其强制转换为FrameLayout,java,android,android-layout,android-fragments,Java,Android,Android Layout,Android Fragments,我有一个片段,带有一个图像按钮和一个框架布局。创建片段时,它会向framelayout添加一个cameraview。下面是片段的xml: <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="mat
片段
,带有一个图像按钮
和一个框架布局
。创建片段时,它会向framelayout添加一个cameraview。下面是片段的xml:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">
<ImageButton
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="@+id/watchButton"
android:src="@drawable/wearc"
android:scaleType="fitCenter"
android:padding="0dp"
android:onClick="onPic"
android:contentDescription="@string/watch" />
<FrameLayout
android:id="@+id/camera_view"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:padding="31.2dp">
</FrameLayout>
</LinearLayout>
package com.coralapps.face2face;
import android.app.Fragment;
import android.content.Context;
import android.content.pm.PackageManager;
import android.hardware.Camera;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.FrameLayout;
import android.widget.Toast;
public class CameraFragment extends Fragment {
android.hardware.Camera mCamera;
private CameraView mCameraView = null;
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.camera_fragment, container, false);
setupCamera(v);
return v;
}
public void setupCamera(View v){
try{
mCamera = Camera.open();//you can use open(int) to use different cameras
} catch (Exception e){
Log.d("ERROR", "Failed to get camera: " + e.getMessage());
}
if(mCamera != null) {
mCameraView = new CameraView(getActivity(), mCamera);
FrameLayout camera_view = (FrameLayout) v.findViewById(R.id.camera_view);
camera_view.addView(mCameraView);
}
}
}
我得到的错误是:
android.support.v7.widget.AppCompatImageButton cannot be cast to android.widget.FrameLayout at com.coralapps.face2face.CameraFragment.setupCamera(CameraFragment.java:41)
但在第41行,我链接到R.id.camera_视图,这显然是一个框架布局,而不是一个Imagebutton
我做错什么了吗
编辑:当我删除
imagebutton
bro时,这确实有效,运行这些代码时没有发现错误!但我改变了这一行
public void setupCamera(View v){
try{
mCamera = Camera.open();//you can use open(int) to use different cameras
} catch (Exception e){
Log.d("ERROR", "Failed to get camera: " + e.getMessage());
}
if(mCamera != null) {
//change
// mCameraView = new CameraView(getActivity(), mCamera);
FrameLayout camera_view = (FrameLayout) v.findViewById(R.id.camera_view);
camera_view.addView(mCameraView);
}
}
我认为问题在于,您在
onCreateView
中调用setupCamera(View v)
,并将尚未充气的视图作为参数传入。相反,您应该从创建视图后调用的onResume()
中获取并操作视图。所以你应该调用setupCamera(v)代码>来自onResume()
方法。代码似乎很好。尝试重建项目:转到Build->rebuild Projects,但是我错过了mCameraView的声明?