android 实现加载动画对话框

先来两张效果图

自定义对话框：

public class LoadingProgressDialog extends ProgressDialog {

    private AnimationDrawable mAnimation;
    private Context mContext;
    private ImageView mImageView;
    private String mLoadingTitle;
    private TextView mLoadingTv;
    private int mResid;

    public LoadingProgressDialog(Context context, String content, int id) {
        super(context);
        this.mContext = context;
        this.mLoadingTitle = content;
        this.mResid = id;
        setCanceledOnTouchOutside(true);
    }

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        initView();
        initData();
    }

    private void initData() {

        mImageView.setBackgroundResource(mResid);
        mAnimation = (AnimationDrawable) mImageView.getBackground();
        mImageView.post(new Runnable() {
            @Override
            public void run() {
                mAnimation.start();
            }
        });
        mLoadingTv.setText(mLoadingTitle);

    }

    public void setContent(String str) {
        mLoadingTv.setText(str);
    }

    private void initView() {
        setContentView(R.layout.progress_dialog);
        mLoadingTv = (TextView) findViewById(R.id.loadingTv);
        mImageView = (ImageView) findViewById(R.id.loadingIv);
    }
}

在layout文件夹下建立progress_dialog.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:gravity="center"
    android:layout_gravity="center"
    android:orientation="vertical">

    <ImageView
        android:id="@+id/loadingIv"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" />

    <TextView
        android:id="@+id/loadingTv"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:textColor="#ffffff"
        android:textSize="20sp" />

</LinearLayout>

动画是由一张一张的图片逐帧播放的，里面每一个item就是一张图片，动画有多少帧就有多少张图片，有多少图片就有多少item。

<?xml version="1.0" encoding="utf-8"?>
<animation-list
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:oneshot="false">
    <item
        android:drawable="@drawable/loading_01"
        android:duration="100" />
    <item
        android:drawable="@drawable/loading_02"
        android:duration="100" />
    <item
        android:drawable="@drawable/loading_03"
        android:duration="100" />
    <item
        android:drawable="@drawable/loading_04"
        android:duration="100" />
</animation-list>

LoadingProgressDialog dialog =new LoadingProgressDialog(MainActivity.this, "正在加载中...",R.anim.frame);
//打开
dialog.show();
//隐藏
dialog.dismiss();