Android调用相机拍摄照片并显示到 ImageView控件中

Posted 2020-10-03 liguangsunls

在前面的一篇文章中曾介绍过简单的开启相机照相功能，详见?Android简单调用相机Camera功能，实现打开照相功能?，这一次就会将前面拍摄的照片显示到ImageView中，形成一个完整的效果 看实例 MainActivity.java

package com.example.camera;

import java.io.File;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;

public class MainActivity extends Activity {
/** Called when the activity is first created. */
String SD_CARD_TEMP_DIR;
Bitmap myBitmap;
private ImageView imageView;

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//
SD_CARD_TEMP_DIR = Environment.getExternalStorageDirectory()
+ File.separator + "tmp.jpg";//设定照相后保存的文件名称，相似于缓存文件

imageView = (ImageView)findViewById(R.id.imageView1);
Button btn = (Button) findViewById(R.id.button1);
btn.setOnClickListener(new OnClickListener() {

@Override
public void onClick(View arg0) {
// TODO Auto-generated method stub
Intent cameraIntent = new Intent(
MediaStore.ACTION_IMAGE_CAPTURE);
cameraIntent.putExtra(android.provider.MediaStore.EXTRA_OUTPUT,
Uri.fromFile(new File(SD_CARD_TEMP_DIR)));
startActivityForResult(cameraIntent, 0);
}
});
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
// TODO Auto-generated method stub
super.onActivityResult(requestCode, resultCode, data);
if(requestCode == 0){
Log.d("requestCode", "Need 0");
if(resultCode == RESULT_OK){
Log.d("resultCode", "OK!!!" + SD_CARD_TEMP_DIR);
myBitmap = BitmapFactory.decodeFile(SD_CARD_TEMP_DIR);
imageView.setImageBitmap(myBitmap);
}else{
Log.d("resultCode", "" + resultCode);
}
}else{
Log.d("requestCode", "Not Need");
}
}
}

看一下 ?activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity" >

<Button
android:id="@+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:layout_alignParentRight="true"
android:text="Button" />

<ImageView
android:id="@+id/imageView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="@+id/button1"
android:layout_alignParentLeft="true"
android:layout_alignParentRight="true"
android:layout_alignParentTop="true"
android:src="@drawable/ic_launcher" />

</RelativeLayout>

最好，再配置一下权限吧。看AndroidMainFest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.camera"
android:versionCode="1"
android:versionName="1.0" >

<uses-permission android:name="android.permission.CAMERA" />

<uses-feature android:name="android.hardware.camera" />
<uses-feature android:name="android.hardware.camera.autofocus" />

<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" >
</uses-permission>

<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="16" />

<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />

<application
android:allowBackup="true"
android:hardwareAccelerated="false"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="com.example.camera.MainActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />

<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>

</manifest>

这个地方，还要注意的是 ?android:hardwareAccelerated="false"? 这一句，假设我们不加这一句的情况下。会非常easy出现下面问题 Bitmap too large to be uploaded into a texture 因此。我们须要将硬件加速功能关闭。