ImageView上的Android进度栏 [英] Android Progress bar on ImageView

问题描述

我正在开发一个应用程序，其中用户可以从相机拍摄照片并将其显示在具有图像视图的预览屏幕上.

I am developing an app in which user will take Picture from camera and display it on preview screen having image view.

**CameraCapture.java**

class ButtonClickHandler implements View.OnClickListener 
{
    public void onClick( View view ){
        myVib.vibrate(50);
        startCameraActivity();
    }
}

protected void startCameraActivity()
{
    File filenew = new File( _path );
    Uri outputFileUri = Uri.fromFile( filenew );

    Intent intent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE );
    intent.putExtra( MediaStore.EXTRA_OUTPUT, outputFileUri );
    intent.addFlags(Intent.FLAG_ACTIVITY_NO_ANIMATION);
    startActivityForResult( intent, 0 );
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) 
{   
    switch( resultCode )
    {
        case 0:
            break;

        case -1:
            //pictaken++;

            onPhotoTaken();

            break;
    }
}

protected void onPhotoTaken()
{
    //pictaken=true;

    Intent i = new Intent(CameraCapture.this,Preview.class);
    startActivity(i);
}

在我的预览"课程中，捕获的图片显示在ImageView上

In my Preview class the captured picture is displayed on ImageView

**Preview.java**

File imgFile = new File("/sdcard/DCIM/Camera/test.jpg");
if(imgFile.exists()){

    // Bitmap myBitmap = BitmapFactory.decodeFile(imgFile.getAbsolutePath());

    ImageView myImage = (ImageView) findViewById(R.id.image);
    Bitmap myBitmap = BitmapFactory.decodeFile(imgFile.getAbsolutePath());
    Matrix mat = new Matrix();
    String degree="90";
    mat.postRotate(Integer.parseInt(degree));
    Bitmap bMapRotate = Bitmap.createBitmap(myBitmap, 0, 0,myBitmap.getWidth(),myBitmap.getHeight(), mat, true);
    myImage.setImageBitmap(bMapRotate);
    //myImage.setImageBitmap(myBitmap);

}
_image = ( ImageView ) findViewById( R.id.image );

在从SD卡加载捕获的图像之前，是否有任何方法可以在ImageView上显示进度条. 提前thnx:)

Is there is any way to show progress bar on the ImageView till it load the Captured image from SD card. Thnx in advance :)

推荐答案

将ImageView和Progressbar放在RelativeLayout中.对于您的ProgressBar，使用:

Put your ImageView and Progressbar in a RelativeLayout. For your ProgressBar, use:

android:layout_centerInParent="true"

它将在RelativeLayout中居中放置，即在ImageView上居中.加载图像后，您可能还想隐藏ProgressBar:

Which will center it in the RelativeLayout, meaning over the ImageView. You might also want to hide the ProgressBar when the image has loaded:

progressBar.setVisibility(View.Gone)

加载图像后.

示例代码:

 <RelativeLayout
        android:layout_width="wrap_content"
        android:layout_height="wrap_content">

         <ImageView 
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:adjustViewBounds="true"/>

        <ProgressBar
            style="?android:attr/progressBarStyleSmall"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerInParent="true"
            android:visibility="visible"/>

    </RelativeLayout>

这篇关于ImageView上的Android进度栏的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！