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1.使LinearLayout布局带有方框线；

要想实现LinearLayout布局带有方框线，这个很简单，直接加一个方框线的布局即可。

效果如下：

package com.hsae.audiodemos.view;import android.content.Context;import android.content.res.Resources;import android.content.res.TypedArray;import android.graphics.Canvas;import android.graphics.Color;import android.graphics.Paint;import android.text.Layout;import android.text.TextPaint;import android.util.AttributeSet;import android.widget.LinearLayout;import com.hsae.audiodemos.R;public class TitleBorderLayout extends LinearLayout {   	private static float DEFAULT_TITLE_POSITION_SCALE = 0.48f;	public static int DEFAULT_BORDER_SIZE = 1;	public static int DEFAULT_BORDER_COLOR = Color.BLACK;	public static int DEAFULT_TITLE_COLOR = Color.BLACK;	private int mBorderPaneHeight ;		private Paint mBorderPaint;	private float mBorderSize;		private TextPaint mTextPaint;	private CharSequence mTitle;	private int mTitlePosition;		public TitleBorderLayout(Context context) {   		this(context, null);	}		/**	 * Construct a new TitleBorderLayout with default style, overriding specific style     * attributes as requested.	 * @param context	 * @param attrs	 */	public TitleBorderLayout(Context context, AttributeSet attrs) {   		super(context, attrs);		setWillNotDraw(false);				mBorderPaint = new Paint(Paint.ANTI_ALIAS_FLAG); 		mTextPaint = new TextPaint(Paint.ANTI_ALIAS_FLAG);		Resources res = getResources();		mTextPaint.density = res.getDisplayMetrics().density;				TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.TitleBorderLayout);				mTitle = a.getText(R.styleable.TitleBorderLayout_title);		int titleColor = a.getColor(R.styleable.TitleBorderLayout_titleTextColor, DEAFULT_TITLE_COLOR);		mTextPaint.setColor(titleColor);				float titleTextSize = a.getDimension(R.styleable.TitleBorderLayout_titleTextSize, 0);		if (titleTextSize > 0) {   			mTextPaint.setTextSize(titleTextSize);		}				mTitlePosition = a.getDimensionPixelSize(R.styleable.TitleBorderLayout_titlePosition, -1); 		mBorderSize = a.getDimensionPixelSize(R.styleable.TitleBorderLayout_borderSize, DEFAULT_BORDER_SIZE);				int borderColor = a.getColor(R.styleable.TitleBorderLayout_borderColor, DEFAULT_BORDER_COLOR);		mBorderPaint.setColor(borderColor);				a.recycle();	}		/**	 * Get the color of border.	 * @return	 */	public int getBorderColor() {   		return mBorderPaint.getColor();	} 	/**	 * Set the color of border.	 * @param borderColor	 */	public void setBorderColor(int borderColor) {   		mBorderPaint.setColor(borderColor);		requestLayout();	} 	/**	 * Get the size of border.	 * @return	 */	public float getBorderSize() {   		return mBorderSize;	} 	/**	 * Set the size of border.	 * @param borderSize	 */	public void setBorderSize(float borderSize) {   		mBorderSize = borderSize;		requestLayout();	} 	/**	 * Get the color of title.	 * @return	 */	public int getTitleColor() {   		return mTextPaint.getColor();	} 	/**	 * Set the color of title.	 * @param titleColor	 */	public void setTitleColor(int titleColor) {   		mTextPaint.setColor(titleColor);		requestLayout();	} 	/**	 * Get the size of title.	 * @return	 */	public float getTitleTextSize() {   		return mTextPaint.getTextSize();	} 	/**	 * Set the size of title.	 * @param titleTextSize	 */	public void setTitleTextSize(float titleTextSize) {   		mTextPaint.setTextSize(titleTextSize);		requestLayout();	}		/**	 * Get the title.	 * @return	 */	public CharSequence getTitle() {   		return mTitle;	} 	/**	 * Set the title which will be shown on the top of border pane. 	 * @param title	 */	public void setTitle(CharSequence title) {   		mTitle = title;		requestLayout();	}		/**	 * Get the position of title.	 * @return	 */	public int getTitlePosition() {   		return mTitlePosition;	} 	/**	 * Set the position of title where the paint will start to draw.	 * @param titlePosition	 */	public void setTitlePosition(int titlePosition) {   		mTitlePosition = titlePosition;		requestLayout();	} 	/**	 * Get the height of border pane, it's different from the layout height!	 * @return	 */	public int getBorderPaneHeight() {   		return mBorderPaneHeight;	} 	/**	 * Draw the title border	 * @param canvas 	 */	@Override	protected void onDraw(Canvas canvas) {   		super.onDraw(canvas);				Paint.FontMetrics fm = mTextPaint.getFontMetrics();		final float titleHeight =  fm.descent - fm.ascent; 		final CharSequence titleText = (mTitle == null) ? "" : mTitle;		final float titleWidth = Layout.getDesiredWidth(titleText, mTextPaint);				final int width = getWidth();		final int height = getHeight();				if (mTitlePosition <= 0 || mTitlePosition + titleWidth > width) {   			mTitlePosition = (int) (DEFAULT_TITLE_POSITION_SCALE * width); 		}				final float topBorderStartY = titleHeight / 3f - mBorderSize / 2;				mBorderPaneHeight = (int) Math.ceil(height - topBorderStartY);	    /* draw border*/		// top		canvas.drawRect(0, topBorderStartY, mTitlePosition, topBorderStartY + mBorderSize, mBorderPaint);		canvas.drawText(titleText.toString(), mTitlePosition, titleHeight / 3 * 2f, mTextPaint); //title		canvas.drawRect(mTitlePosition + titleWidth, topBorderStartY, width, topBorderStartY + mBorderSize, mBorderPaint);        // left        canvas.drawRect(0, topBorderStartY, mBorderSize, height, mBorderPaint);        // right        canvas.drawRect(width - mBorderSize, topBorderStartY, width, height, mBorderPaint);        // down        canvas.drawRect(0, height - mBorderSize, width, height, mBorderPaint);	}}

attrs.xml

属性使用方法：

app:title="布局1"app:titleTextSize="16dp"

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