1.ClipDrawable(裁剪)

ClipDrawable對應於標籤< clip >，它可以根據自己當前的level來裁剪另一個Drawable.

1. 語法

<?xml version="1.0" encoding="utf-8"?>
<clip
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:drawable="@drawable/drawable_resource"
    android:clipOrientation=["horizontal" | "vertical"]
    android:gravity=["top" | "bottom" | "left" | "right" | "center_vertical" |
                     "fill_vertical" | "center_horizontal" | "fill_horizontal" |
                     "center" | "fill" | "clip_vertical" | "clip_horizontal"] />
 

?：android:clipOrientation與android:gravity 配合使用。 android:clipOrientation可選屬性：

android:gravity可選屬性：

2. 使用：新建xml

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

表示將in資源垂直底部裁剪

3. 佈局中引用

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/view"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <ImageView
        android:id="@+id/iv1"
        android:layout_width="match_parent"
        android:layout_height="300dp"
        android:src="@drawable/clip_bg" />

</LinearLayout>

4. Activity中設定level

public class MainActivity extends AppCompatActivity {

    private ImageView imageView;
    private int level = 0;
    private SeekBar seekBar;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
            ClipDrawable clipDrawable = (ClipDrawable) imageView.getDrawable();
            clipDrawable.setLevel(8000);
    }
}

5. 跟隨SeekBar進度裁剪圖片的Demo

• 新建資源
• 佈局引用如上,新增程式碼

 <SeekBar
        android:id="@+id/seekBar"
        android:max="100"
        android:min="0"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        tools:ignore="UnusedAttribute" />

• Activity中監聽SeekBar的進度並設定level

public class MainActivity extends AppCompatActivity {

    private ImageView imageView;
    private SeekBar seekBar;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        imageView = findViewById(R.id.iv1);

        seekBar =findViewById(R.id.seekBar);
        seekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
            @Override
            public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
                ClipDrawable clipDrawable = (ClipDrawable) imageView.getDrawable();
                //10000 * (progress/100）= 100*progress
                clipDrawable.setLevel(progress*100);
            }
            @Override
            public void onStartTrackingTouch(SeekBar seekBar) {
            }
            @Override
            public void onStopTrackingTouch(SeekBar seekBar) {
            }
        });
    }
}

• 效果

2.ScaleDrawable(縮放)

ScaleDrawable對應標籤< scale >，它可以根據自己的level將指定的Drawable縮放到一定比例。要使ScaleDrawable可見，讓level != 0

1. 語法

<?xml version="1.0" encoding="utf-8"?>
<scale
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:drawable="@drawable/drawable_resource"
    android:scaleGravity=["top" | "bottom" | "left" | "right" | "center_vertical" |
                          "fill_vertical" | "center_horizontal" | "fill_horizontal" |
                          "center" | "fill" | "clip_vertical" | "clip_horizontal"]
    android:scaleHeight="percentage"
    android:scaleWidth="percentage" />

android:scaleHeight    對高進行縮放
android:scaleWidth     對寬進行縮放

android:scaleGravity屬性如下：

2. 新建xml

<?xml version="1.0" encoding="utf-8"?>
<scale xmlns:android="http://schemas.android.com/apk/res/android"
    android:drawable="@drawable/in"
    android:scaleHeight="50%"
    android:scaleWidth="50%"
    android:scaleGravity="center"
    />

3. 引用

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/view"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <ImageView
        android:id="@+id/iv2"
        android:layout_width="match_parent"
        android:layout_height="300dp"
        android:src="@drawable/scale_bg" />
</LinearLayout>

5. 設定level

public class MainActivity extends AppCompatActivity {
    private ImageView imageView;
    private ImageView imageView1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        imageView1 = findViewById(R.id.iv2);
        ScaleDrawable scaleDrawable = (ScaleDrawable) imageView1.getDrawable();
        scaleDrawable.setLevel(1);
    }
}

level 範圍 0-10000

6. 效果