Android自定义组件之自动换行View - 儒雅小生

做Android这么长时间，对自定义组件这块知识了解的很少。之前公司项目里有个模块需求是自动换行，今天重新写个组件实现这个效果。

      效果图如下：

组件是继承的ViewGroup,在用的时候调用addView方法把TextView加进去，然后该组件会把textview放到合适的位置。

WordWrapView.java

public class WordWrapView extends ViewGroup {  private static final int PADDING_HOR = 10;//水平方向padding  private static final int PADDING_VERTICAL = 5;//垂直方向padding  private static final int SIDE_MARGIN = 10;//左右间距  private static final int TEXT_MARGIN = 10;  /**   * @param context   */  public WordWrapView(Context context) {    super(context);  }    /**   * @param context   * @param attrs   * @param defStyle   */  public WordWrapView(Context context, AttributeSet attrs, int defStyle) {    super(context, attrs, defStyle);  }  /**   * @param context   * @param attrs   */  public WordWrapView(Context context, AttributeSet attrs) {    super(context, attrs);  }  @Override  protected void onLayout(boolean changed, int l, int t, int r, int b) {    int childCount = getChildCount();    int autualWidth = r - l;    int x = SIDE_MARGIN;// 横坐标开始    int y = 0;//纵坐标开始    int rows = 1;    for(int i=0;i<childCount;i++){      View view = getChildAt(i);      view.setBackgroundColor(Color.GREEN);      int width = view.getMeasuredWidth();      int height = view.getMeasuredHeight();      x += width+TEXT_MARGIN;      if(x>autualWidth){        x = width+SIDE_MARGIN;        rows++;      }      y = rows*(height+TEXT_MARGIN);      if(i==0){        view.layout(x-width-TEXT_MARGIN, y-height, x-TEXT_MARGIN, y);      }else{        view.layout(x-width, y-height, x, y);      }    }  };  @Override  protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {    int x = 0;//横坐标    int y = 0;//纵坐标    int rows = 1;//总行数    int specWidth = MeasureSpec.getSize(widthMeasureSpec);    int actualWidth = specWidth - SIDE_MARGIN * 2;//实际宽度    int childCount = getChildCount();    for(int index = 0;index<childCount;index++){      View child = getChildAt(index);      child.setPadding(PADDING_HOR, PADDING_VERTICAL, PADDING_HOR, PADDING_VERTICAL);      child.measure(MeasureSpec.UNSPECIFIED, MeasureSpec.UNSPECIFIED);      int width = child.getMeasuredWidth();      int height = child.getMeasuredHeight();      x += width+TEXT_MARGIN;      if(x>actualWidth){//换行        x = width;        rows++;      }      y = rows*(height+TEXT_MARGIN);    }    setMeasuredDimension(actualWidth, y);  }}

View Code

MainActivity.java

public class MainActivity extends Activity {  private WordWrapView wordWrapView;  private String[] strs = new String[] { "哲学系", "新疆维吾尔族自治区", "新闻学", "心理学",      "犯罪心理学", "明明白白", "西方文学史", "计算机", "掌声", "心太软", "生命",      "程序开发" };  @Override  protected void onCreate(Bundle savedInstanceState) {    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_main);    wordWrapView = (WordWrapView) this.findViewById(R.id.view_wordwrap);    for (int i = 0; i < 12; i++) {      TextView textview = new TextView(this);      textview.setText(strs[i]);      wordWrapView.addView(textview);    }  }}

View Code

activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"  xmlns:tools="http://schemas.android.com/tools"  android:layout_width="match_parent"  android:layout_height="match_parent"  tools:context=".MainActivity" >  <com.winhoo.viewtest.widget.WordWrapView    android:id="@+id/view_wordwrap"    android:layout_width="wrap_content"    android:layout_height="wrap_content"    android:layout_centerHorizontal="true"    /></RelativeLayout>

activity_main.xml

欢迎批评指正！谢谢。