Android 将ImageView更改为黑白而不是可绘制视图
我想将imageview更改为黑白,而不是drawable。这是因为用户拍摄了一张照片,它会显示在imageview中。如果您知道如何执行此操作,我将不胜感激,谢谢Android 将ImageView更改为黑白而不是可绘制视图,android,Android,我想将imageview更改为黑白,而不是drawable。这是因为用户拍摄了一张照片,它会显示在imageview中。如果您知道如何执行此操作,我将不胜感激,谢谢 package com.example.triptych4; import java.io.File; import android.app.Activity; import android.content.ContentResolver; import android.content.Context; import andro
package com.example.triptych4;
import java.io.File;
import android.app.Activity;
import android.content.ContentResolver;
import android.content.Context;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Color;
import android.graphics.ColorMatrix;
import android.graphics.ColorMatrixColorFilter;
import android.graphics.drawable.Drawable;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.Button;
import android.widget.Gallery;
import android.widget.ImageButton;
import android.widget.ImageView;
import android.widget.Toast;
public class MainActivity extends Activity {
// label our logs "CameraApp3"
private static String logtag = "CameraApp3";
// tells us which camera to take a picture from
private static int TAKE_PICTURE = 1;
// empty variable to hold our image Uri once we store it
private Uri imageUri;
private Integer[] pics = { R.drawable.android, R.drawable.android3d,
R.drawable.background3 };
{
ImageView imageView = (ImageView)findViewById(R.id.imageView1);
ColorMatrix matrix = new ColorMatrix();
matrix.setSaturation(0);
ColorMatrixColorFilter filter = new ColorMatrixColorFilter(matrix);
imageView.setColorFilter(filter);
}
private ImageView imageView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Gallery gallery = (Gallery) findViewById(R.id.gallery1);
gallery.setAdapter(new ImageAdapter(this));
imageView = (ImageView) findViewById(R.id.imageView1);
gallery.setOnItemClickListener( new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> arg0, View arg1, int arg2,
long arg3) {
Toast.makeText(getApplicationContext(), "pic:" + arg2,
Toast.LENGTH_SHORT).show();
imageView.setImageResource(pics[arg2]);
}
});
// look for the button we set in the view
ImageButton cameraButton = (ImageButton)
findViewById(R.id.button_camera);
// set a listener on the button
cameraButton.setOnClickListener(cameraListener);
}
// set a new listener
private OnClickListener cameraListener = new OnClickListener() {
public void onClick(View v) {
// open the camera and pass in the current view
takePhoto(v);
}
};
public void takePhoto(View v) {
// tell the phone we want to use the camera
Intent intent = new Intent("android.media.action.IMAGE_CAPTURE");
// create a new temp file called pic.jpg in the "pictures" storage area of the phone
File photo = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES), "pic.jpg");
// take the return data and store it in the temp file "pic.jpg"
intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(photo));
// stor the temp photo uri so we can find it later
imageUri = Uri.fromFile(photo);
// start the camera
startActivityForResult(intent, TAKE_PICTURE);
}
@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;
}
public class ImageAdapter extends BaseAdapter{
private Context context;
int imageBackground;
public ImageAdapter(Context context){
this.context = context;
}
@Override
public int getCount() {
// TODO Auto-generated method stub
return pics.length;
}
@Override
public Object getItem(int arg0) {
// TODO Auto-generated method stub
return arg0;
}
@Override
public long getItemId(int arg0) {
// TODO Auto-generated method stub
return arg0;
}
@Override
public View getView(int arg0, View arg1, ViewGroup arg2) {
// TODO Auto-generated method stub
ImageView imageView =new ImageView(context);
imageView.setImageResource(pics[arg0]);
return imageView;
}
}
// override the original activity result function
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
// call the parent
super.onActivityResult(requestCode, resultCode, data);
switch(requestCode) {
// if the requestCode was equal to our camera code (1) then...
case 1:
// if the user took a photo and selected the photo to use
if(resultCode == Activity.RESULT_OK) {
// get the image uri from earlier
Uri selectedImage = imageUri;
// notify any apps of any changes we make
getContentResolver().notifyChange(selectedImage, null);
// get the imageView we set in our view earlier
ImageButton imageButton = (ImageButton)findViewById(R.id.button_camera);
// create a content resolver object which will allow us to access the image file at the uri above
ContentResolver cr = getContentResolver();
// create an empty bitmap object
Bitmap bitmap;
try {
// get the bitmap from the image uri using the content resolver api to get the image
bitmap = android.provider.MediaStore.Images.Media.getBitmap(cr, selectedImage);
// set the bitmap to the image view
imageButton.setImageBitmap(bitmap);
// notify the user
Toast.makeText(MainActivity.this, selectedImage.toString(), Toast.LENGTH_LONG).show();
} catch(Exception e) {
// notify the user
Toast.makeText(MainActivity.this, "failed to load", Toast.LENGTH_LONG).show();
Log.e(logtag, e.toString());
}
}
}
}
}
package com.example.triptych4;
导入java.io.File;
导入android.app.Activity;
导入android.content.ContentResolver;
导入android.content.Context;
导入android.content.Intent;
导入android.graphics.Bitmap;
导入android.graphics.BitmapFactory;
导入android.graphics.Color;
导入android.graphics.ColorMatrix;
导入android.graphics.ColorMatrixColorFilter;
导入android.graphics.drawable.drawable;
导入android.net.Uri;
导入android.os.Bundle;
导入android.os.Environment;
导入android.provider.MediaStore;
导入android.util.Log;
导入android.view.Menu;
导入android.view.view;
导入android.view.view.OnClickListener;
导入android.view.ViewGroup;
导入android.widget.AdapterView;
导入android.widget.BaseAdapter;
导入android.widget.Button;
导入android.widget.Gallery;
导入android.widget.ImageButton;
导入android.widget.ImageView;
导入android.widget.Toast;
公共类MainActivity扩展了活动{
//将日志标记为“CameraApp3”
私有静态字符串logtag=“CameraApp3”;
//告诉我们从哪个相机拍照
私有静态int TAKE_PICTURE=1;
//存储图像Uri后,保留该Uri的空变量
私有Uri-imageUri;
私有整数[]pics={R.drawable.android,R.drawable.android3d,
R.drawable.background3};
{
ImageView ImageView=(ImageView)findViewById(R.id.imageView1);
ColorMatrix=新的ColorMatrix();
基质饱和(0);
ColorMatrixColorFilter过滤器=新的ColorMatrixColorFilter(矩阵);
设置颜色过滤器(过滤器);
}
私人影像视图;
@凌驾
创建时受保护的void(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
画廊画廊=(画廊)findViewById(R.id.gallery1);
gallery.setAdapter(新的ImageAdapter(本));
imageView=(imageView)findViewById(R.id.imageView1);
gallery.setOnItemClickListener(新的AdapterView.OnItemClickListener(){
@凌驾
公共链接(AdapterView arg0、视图arg1、内部arg2、,
长arg3){
Toast.makeText(getApplicationContext(),“pic:+arg2,
吐司。长度(短)。show();
setImageResource(pics[arg2]);
}
});
//查找我们在视图中设置的按钮
ImageButton cameraButton=(ImageButton)
findViewById(R.id.按钮\摄像机);
//在按钮上设置侦听器
setOnClickListener(cameraListener);
}
//设置一个新的侦听器
private OnClickListener cameraListener=新OnClickListener(){
公共void onClick(视图v){
//打开相机并在当前视图中通过
拍照(五);
}
};
公众照片(视图五){
//告诉电话我们想用摄像机
Intent Intent=新的Intent(“android.media.action.IMAGE_-CAPTURE”);
//在手机的“图片”存储区创建一个名为pic.jpg的新临时文件
File photo=新文件(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES),“pic.jpg”);
//获取返回数据并将其存储在临时文件“pic.jpg”中
intent.putExtra(MediaStore.EXTRA_输出,Uri.fromFile(照片));
//存储临时照片uri,以便我们以后可以找到它
imageUri=Uri.fromFile(照片);
//启动摄像机
startActivityForResult(意图,拍照);
}
@凌驾
公共布尔onCreateOptions菜单(菜单){
//为菜单充气;这会将项目添加到操作栏(如果存在)。
getMenuInflater().充气(R.menu.main,menu);
返回true;
}
公共类ImageAdapter扩展了BaseAdapter{
私人语境;
int图像背景;
公共ImageAdapter(上下文){
this.context=上下文;
}
@凌驾
public int getCount(){
//TODO自动生成的方法存根
返回图片长度;
}
@凌驾
公共对象getItem(int arg0){
//TODO自动生成的方法存根
返回arg0;
}
@凌驾
公共长getItemId(int arg0){
//TODO自动生成的方法存根
返回arg0;
}
@凌驾
公共视图getView(int arg0、视图arg1、视图组arg2){
//TODO自动生成的方法存根
ImageView ImageView=新的ImageView(上下文);
setImageResource(pics[arg0]);
返回图像视图;
}
}
//重写原始“活动结果”函数
@凌驾
ActivityResult上的公共void(int请求代码、int结果代码、意图数据){
//打电话给家长
super.onActivityResult(请求代码、结果代码、数据);
开关(请求代码){
//如果请求代码等于我们的相机代码(1),那么。。。
案例1:
//如果用户拍摄照片并选择要使用的照片
if(resultCode==Activity.RESULT\u确定){
//从早期版本获取图像uri
Uri selectedImage=imageUri;
//将我们所做的任何更改通知任何应用程序
getContentResolver().notifyChange(SelecteImage,null);
//获取之前在视图中设置的imageView
ImageButton ImageButton=(ImageButton)findViewById(R.id.button\U摄像头);
//创建一个内容解析器对象,它将允许我们访问上面uri处的图像文件
C
05-22 10:26:07.156: D/AndroidRuntime(24617): Shutting down VM
05-22 10:26:07.156: W/dalvikvm(24617): threadid=1: thread exiting with uncaught exception (group=0x41cac700)
05-22 10:26:07.156: E/AndroidRuntime(24617): FATAL EXCEPTION: main
05-22 10:26:07.156: E/AndroidRuntime(24617): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.triptych4/com.example.triptych4.MainActivity}: java.lang.NullPointerException
05-22 10:26:07.156: E/AndroidRuntime(24617): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2219)
05-22 10:26:07.156: E/AndroidRuntime(24617): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2349)
05-22 10:26:07.156: E/AndroidRuntime(24617): at android.app.ActivityThread.access$700(ActivityThread.java:159)
05-22 10:26:07.156: E/AndroidRuntime(24617): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1316)
05-22 10:26:07.156: E/AndroidRuntime(24617): at android.os.Handler.dispatchMessage(Handler.java:99)
05-22 10:26:07.156: E/AndroidRuntime(24617): at android.os.Looper.loop(Looper.java:137)
05-22 10:26:07.156: E/AndroidRuntime(24617): at android.app.ActivityThread.main(ActivityThread.java:5419)
05-22 10:26:07.156: E/AndroidRuntime(24617): at java.lang.reflect.Method.invokeNative(Native Method)
05-22 10:26:07.156: E/AndroidRuntime(24617): at java.lang.reflect.Method.invoke(Method.java:525)
05-22 10:26:07.156: E/AndroidRuntime(24617): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1209)
05-22 10:26:07.156: E/AndroidRuntime(24617): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1025)
05-22 10:26:07.156: E/AndroidRuntime(24617): at dalvik.system.NativeStart.main(Native Method)
05-22 10:26:07.156: E/AndroidRuntime(24617): Caused by: java.lang.NullPointerException
05-22 10:26:07.156: E/AndroidRuntime(24617): at android.app.Activity.findViewById(Activity.java:1914)
05-22 10:26:07.156: E/AndroidRuntime(24617): at com.example.triptych4.MainActivity.<init>(MainActivity.java:47)
05-22 10:26:07.156: E/AndroidRuntime(24617): at java.lang.Class.newInstanceImpl(Native Method)
05-22 10:26:07.156: E/AndroidRuntime(24617): at java.lang.Class.newInstance(Class.java:1130)
05-22 10:26:07.156: E/AndroidRuntime(24617): at android.app.Instrumentation.newActivity(Instrumentation.java:1078)
05-22 10:26:07.156: E/AndroidRuntime(24617): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2210)
05-22 10:26:07.156: E/AndroidRuntime(24617): ... 11 more
ImageView imageView = (ImageView)findViewById(R.id.imageView);
...
ColorMatrix matrix = new ColorMatrix();
matrix.setSaturation(0);
ColorMatrixColorFilter filter = new ColorMatrixColorFilter(matrix);
imageView.setColorFilter(filter);