Question

我在一些Android教程之后写了一堂课。该类存储为＆＃34; TodoList的\ SRC \ com.example.todolist \ ToDoListItemView.java＆＃34;

package com.example.todolist;

import android.content.Context;
import android.content.res.Resources;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.util.AttributeSet;
import android.widget.TextView;

public class ToDoListItemView extends TextView{

private Paint marginPaint,linePaint;
private int paperColor;
private float margin;

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

public ToDoListItemView(Context context, AttributeSet attrs) {
    super(context, attrs);
    init();
}

public ToDoListItemView(Context context) {
    super(context);
    init();
}

private void init(){
    Resources myResources = getResources();

    //Create the paint resources to be used in the onDraw method
    marginPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
    marginPaint.setColor(myResources.getColor(R.color.notepad_margin));
    linePaint = new Paint(Paint.ANTI_ALIAS_FLAG);
    linePaint.setColor(myResources.getColor(R.color.notepad_lines));

    //Get paper background color and margin width
    paperColor = myResources.getColor(R.color.notepad_paper);
    margin = myResources.getDimension(R.dimen.notepad_margin);
}

@Override
public void onDraw(Canvas canvas) {
    canvas.drawColor(paperColor);

    //Draw ruled lines
    canvas.drawLine(0, 0, 0, getMeasuredHeight(), linePaint);
    canvas.drawLine(0, getMeasuredHeight(), getMeasuredWidth(), getMeasuredHeight(), linePaint);

    //Draw margin
    canvas.drawLine(margin, 0, margin, getMeasuredHeight(), marginPaint);

    //Move text across from the margin
    canvas.save();
    canvas.translate(margin, 0);

    //Render
    super.onDraw(canvas);
    canvas.restore();
}

}

当我在中创建新布局时＆＃34; TodoList的\ RES \布局＆＃34; 任何名字，我输入＆＃34; com。＆＃34;，它会自动推荐我的路径＆＃34; com.example.todolist.ToDoListItemView＆＃34; 我想知道我的＆＃34; ToDoListItemView.java＆＃34;中有什么区别特征。让日食认为它是一种布局？

Answer 1

建议ToDoListItemView，因为它是CustomView。

Eclipse认识到您的班级ToDoListItemView派生自TextView 派生自 View。

所有扩展View的类都可以在布局中使用。

如果您的课程没有以某种方式延伸View，则无法将其放入布局。

ADT如何确定这是一个布局？

1 个答案: