Android Custom Loading

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Android开发中我们经常会用到各种各样的loading,于是自己总结了常用的loading并分享出来。首先来看下具体效果图:

完整源码参见:stormzhang / CustomLoading

下面主要说下代码的关键部分:

1. Frame Loading

第一个就是在app中常见的loading效果,主要是用帧动画实现的,所谓帧动画就是一组组图片顺序播放; 下面直接看下代码实现:

首先在drawable文件夹下建立一个xml文件,内容如下:

frame_loading.xml
<?xml version="1.0" encoding="UTF-8"?>
<animation-list xmlns:android="http://schemas.android.com/apk/res/android"
    android:oneshot="false" >

    <item android:duration="150">
        <clip
            android:clipOrientation="horizontal"
            android:drawable="@drawable/loading_01"
            android:gravity="left" />
    </item>
    <item android:duration="150">
        <clip
            android:clipOrientation="horizontal"
            android:drawable="@drawable/loading_02"
            android:gravity="left" />
    </item>
    <item android:duration="150">
        <clip
            android:clipOrientation="horizontal"
            android:drawable="@drawable/loading_03"
            android:gravity="left" />
    </item>
    <item android:duration="150">
        <clip
            android:clipOrientation="horizontal"
            android:drawable="@drawable/loading_04"
            android:gravity="left" />
    </item>
    <item android:duration="150">
        <clip
            android:clipOrientation="horizontal"
            android:drawable="@drawable/loading_05"
            android:gravity="left" />
    </item>
    <item android:duration="150">
        <clip
            android:clipOrientation="horizontal"
            android:drawable="@drawable/loading_06"
            android:gravity="left" />
    </item>
    <item android:duration="150">
        <clip
            android:clipOrientation="horizontal"
            android:drawable="@drawable/loading_07"
            android:gravity="left" />
    </item>
    <item android:duration="150">
        <clip
            android:clipOrientation="horizontal"
            android:drawable="@drawable/loading_08"
            android:gravity="left" />
    </item>
    <item android:duration="150">
        <clip
            android:clipOrientation="horizontal"
            android:drawable="@drawable/loading_09"
            android:gravity="left" />
    </item>
    <item android:duration="150">
        <clip
            android:clipOrientation="horizontal"
            android:drawable="@drawable/loading_10"
            android:gravity="left" />
    </item>
    <item android:duration="150">
        <clip
            android:clipOrientation="horizontal"
            android:drawable="@drawable/loading_11"
            android:gravity="left" />
    </item>
    <item android:duration="150">
        <clip
            android:clipOrientation="horizontal"
            android:drawable="@drawable/loading_12"
            android:gravity="left" />
    </item>

</animation-list>

注意上面item下得clip标签,这个是必须的,不然不同的屏幕尺寸适配会有问题。然后在布局文件里这样调用:

<ProgressBar
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:indeterminateDrawable="@drawable/frame_loading" />

2. Rotate Loading

第二种主要是用rotate动画来实现的,具体代码如下:

rotate_loading.xml
<rotate xmlns:android="http://schemas.android.com/apk/res/android"
    android:fromDegrees="0"
    android:interpolator="@android:anim/accelerate_decelerate_interpolator"
    android:pivotX="50%"
    android:pivotY="50%"
    android:toDegrees="360" >

    <bitmap
        android:antialias="true"
        android:filter="true"
        android:src="@drawable/loading_360" />

</rotate>

然后调用方法和第一种一样。

<ProgressBar
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:indeterminateDrawable="@drawable/rotate_loading" />

3. Clip Loading

第三种loading的是自定义了一个组件,主要用到了ClipDrawable的setLevel()方法,代码如下:

public class CustomClipLoading extends FrameLayout {

	private static final int MAX_PROGRESS = 10000;
	private ClipDrawable mClipDrawable;
	private int mProgress = 0;
	private boolean running;
	private Handler handler = new Handler() {
		@Override
		public void handleMessage(Message msg) {
			// 如果消息是本程序发送的
			if (msg.what == 0x123) {
				mClipDrawable.setLevel(mProgress);
			}
		}
	};

	
	public CustomClipLoading(Context context) {
		this(context, null, 0);
	}

	public CustomClipLoading(Context context, AttributeSet attrs) {
		this(context, attrs, 0);
	}

	public CustomClipLoading(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
		init(context);
	}

	private void init(Context context) {
		View view = LayoutInflater.from(context).inflate(layout.custom_loading, null);
		addView(view);
		ImageView imageView = (ImageView) findViewById(id.iv_progress);
		mClipDrawable = (ClipDrawable) imageView.getDrawable();
		
		Thread s = new Thread(r);
		s.start();
	}

	public void stop() {
		mProgress = 0;
		running = false;
	}

	Runnable r = new Runnable() {
		@Override
		public void run() {
			running = true;
			while (running) {
				handler.sendEmptyMessage(0x123);
				if (mProgress > MAX_PROGRESS) {
					mProgress = 0;
				}
				mProgress += 100;
				try {
					Thread.sleep(18);
				} catch (InterruptedException e) {
					e.printStackTrace();
				}
			}
		}
	};
}

其中custom_loading布局文件的内容如下:

custom_loading.xml
<?xml version="1.0" encoding="utf-8"?>
<ImageView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/iv_progress"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_gravity="center"
    android:background="@drawable/loading_bg"
    android:paddingLeft="3dp"
    android:paddingTop="3dp"
    android:scaleType="centerInside"
    android:src="@drawable/clip_loading" />

然后clip_loading的内容如下:

clip_loading.xml
<?xml version="1.0" encoding="utf-8"?>
<clip xmlns:android="http://schemas.android.com/apk/res/android"
    android:clipOrientation="vertical"
    android:drawable="@drawable/loading_progress"
    android:gravity="bottom" >
</clip>

至此这个组件就定义好了,那么接下来就是在avtivity布局文件的使用了:

<com.storm.ui.CustomClipLoading
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />

4. Progress Wheel

第四和第五种loading只要是用到了一个开源的项目ProgressWheel,使用方法也很简单,具体见项目说明。