在Android中调用自定义View的onDraw()方法

时间:2013-03-13 09:32:47

标签: android android-custom-view

我为Calendar创建了一个CustomView。我有一个onDraw方法来绘制日历中的文本。我想点击它时改变当天文字的颜色。我怎样才能实现它?

CalendarView.java:

package com.example.calendar_module;

import java.util.Calendar;

import android.app.ActionBar.LayoutParams;
import android.content.Context;
import android.content.res.Resources;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.util.MonthDisplayHelper;
import android.view.MotionEvent;
import android.widget.ImageView;

public class CalendarView extends ImageView {

private static int WEEK_TOP_MARGIN = 0;
private static int WEEK_LEFT_MARGIN = 05;
private static int CELL_WIDTH = 20;
private static int CELL_HEIGH = 20;
private static int CELL_MARGIN_TOP = 05;
private static int CELL_MARGIN_LEFT = 29;
private static float CELL_TEXT_SIZE;
private static int CALENDAR_WIDTH;
private static int CALENDAR_HEIGHT;

private static final String TAG = "CalendarView"; 
private String[] mDayString = {"Sun","Mon","Tue","Wed","Thu","Fri","Sat"};
private Calendar mRightNow = null;
private Drawable mWeekTitle = null;
private Cell mToday = null;
private Cell[][] mCells = new Cell[6][7];
private Cell[] mDayCells = new Cell[7];
private OnCellTouchListener mOnCellTouchListener = null;
MonthDisplayHelper mHelper;
Drawable mDecoration = null;

public interface OnCellTouchListener {
    public void onTouch(Cell cell);
}

public CalendarView(Context context) {
    this(context, null);
}

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

public CalendarView(Context context, AttributeSet attrs, int defStyle) {
    super(context, attrs, defStyle);
    mDecoration = context.getResources().getDrawable(R.drawable.typeb_calendar_today);      
    initCalendarView();
}

private void initCalendarView() {

    mRightNow = Calendar.getInstance();
    // prepare static vars

    Resources res = getResources();
    WEEK_TOP_MARGIN  = (int) res.getDimension(R.dimen.week_top_margin);
    WEEK_LEFT_MARGIN = (int) res.getDimension(R.dimen.week_left_margin);

    CELL_WIDTH = (int) res.getDimension(R.dimen.cell_width);
    CELL_HEIGH = (int) res.getDimension(R.dimen.cell_heigh);
    CELL_MARGIN_TOP = (int) res.getDimension(R.dimen.cell_margin_top);
    CELL_MARGIN_LEFT = (int) res.getDimension(R.dimen.cell_margin_left);
   //       CALENDAR_HEIGHT = 700;
  //        CALENDAR_WIDTH = 700;
  //        
    CALENDAR_HEIGHT = (int) res.getDimension(R.dimen.calendar_height);
    CALENDAR_WIDTH = (int) res.getDimension(R.dimen.calendar_width);

    System.out.println("Width and Hight :"+CALENDAR_WIDTH+" "+CALENDAR_HEIGHT);
    System.out.println("Dimen Width and Height : "+R.dimen.calendar_width+" "+R.dimen.calendar_height);

    CELL_TEXT_SIZE = res.getDimension(R.dimen.cell_text_size);
    // set background
  //        setImageResource(R.drawable.background);
    mWeekTitle = res.getDrawable(R.drawable.calendar_week);

    mHelper = new MonthDisplayHelper(mRightNow.get(Calendar.YEAR), mRightNow.get(Calendar.MONTH));


}

private void initCells() {

    class _calendar {
        public int day;
        public boolean thisMonth;
        public _calendar(int d, boolean b) {
            day = d;
            thisMonth = b;
        }
        public _calendar(int d) {
            this(d, false);
        }
    };
    _calendar tmp[][] = new _calendar[6][7];

    for(int i=0; i<tmp.length; i++) {
        int n[] = mHelper.getDigitsForRow(i);
        for(int d=0; d<n.length; d++) {
            if(mHelper.isWithinCurrentMonth(i,d))
                tmp[i][d] = new _calendar(n[d], true);
            else
                tmp[i][d] = new _calendar(n[d]);

        }
    }

    Calendar today = Calendar.getInstance();
    int thisDay = 0;
    mToday = null;
    if(mHelper.getYear()==today.get(Calendar.YEAR) && mHelper.getMonth()==today.get(Calendar.MONTH)) {
        thisDay = today.get(Calendar.DAY_OF_MONTH);
    }


    // build cells
    Rect Bound = new Rect(CELL_MARGIN_LEFT, CELL_MARGIN_TOP, CELL_WIDTH+CELL_MARGIN_LEFT, CELL_HEIGH+CELL_MARGIN_TOP);
   //       for( int i=0 ; i < 7 ; i++ )
   //       {
   //           
    //          mDayCells[i] = new Cell(mDayString[i],new Rect(Bound),CELL_TEXT_SIZE);
  //            Bound.offset(CELL_WIDTH, 0);
 //         
 //     }
 //     
 //     Bound.offset(0, CELL_HEIGH);      // move to next row and first column
 //     Bound.left = CELL_MARGIN_LEFT;
 //     Bound.right = CELL_MARGIN_LEFT+CELL_WIDTH;
 //     

    for(int week=0; week<mCells.length; week++) {
        for(int day=0; day<mCells[week].length; day++) 
        {

            if(tmp[week][day].thisMonth) {
                if(day==0 || day==6 )
                    mCells[week][day] = new RedCell(tmp[week][day].day, new Rect(Bound), CELL_TEXT_SIZE);
                else 
                    mCells[week][day] = new Cell(tmp[week][day].day, new Rect(Bound), CELL_TEXT_SIZE);
            } else {

                mCells[week][day] = new GrayCell(tmp[week][day].day, new Rect(Bound), CELL_TEXT_SIZE);
            }

            Bound.offset(CELL_WIDTH, 0); // move to next column 

            // get today
            if(tmp[week][day].day==thisDay && tmp[week][day].thisMonth) {
                mToday = mCells[week][day];
                mDecoration.setBounds(mToday.getBound());
            }
        }

        Bound.offset(0, CELL_HEIGH); // move to next row and first column
        Bound.left = CELL_MARGIN_LEFT;
        Bound.right = CELL_MARGIN_LEFT+CELL_WIDTH;

    }       
}

@Override
public void onLayout(boolean changed, int left, int top, int right, int bottom) {
  //        Rect re = getDrawable().getBounds();
  //        WEEK_LEFT_MARGIN = CELL_MARGIN_LEFT = (right-left - re.width()) / 2;
  //        mWeekTitle.setBounds(WEEK_LEFT_MARGIN, WEEK_TOP_MARGIN, WEEK_LEFT_MARGIN+mWeekTitle.getMinimumWidth(), WEEK_TOP_MARGIN+mWeekTitle.getMinimumHeight());

    initCells();
    super.onLayout(changed, left, top, right, bottom);
}

@Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    System.out.println("Width : "+CALENDAR_WIDTH);
    System.out.println("Height : "+CALENDAR_HEIGHT);
    setMeasuredDimension(CALENDAR_WIDTH, CALENDAR_HEIGHT);
  //        setMeasuredDimension(100,200);
}

public void setTimeInMillis(long milliseconds) {
    mRightNow.setTimeInMillis(milliseconds);
    initCells();
    this.invalidate();
}

public int getYear() {
    return mHelper.getYear();
}

public int getMonth() {
    return mHelper.getMonth();
}

public void nextMonth() {
    mHelper.nextMonth();
    initCells();
    invalidate();
}

public void previousMonth() {
    mHelper.previousMonth();
    initCells();
    invalidate();
}

public boolean firstDay(int day) {
    return day==1;
}

public boolean lastDay(int day) {
    return mHelper.getNumberOfDaysInMonth()==day;
}

public void goToday() {
    Calendar cal = Calendar.getInstance();
    mHelper = new MonthDisplayHelper(cal.get(Calendar.YEAR), cal.get(Calendar.MONTH));
    initCells();
    invalidate();
}

public Calendar getDate() {
    return mRightNow;
}

@Override
public boolean onTouchEvent(MotionEvent event) {
    if(mOnCellTouchListener!=null){
        for(Cell[] week : mCells) {
            for(Cell day : week) {
                if(day.hitTest((int)event.getX(), (int)event.getY())) {
                    mOnCellTouchListener.onTouch(day);
                }                       
            }
        }
    }
    return super.onTouchEvent(event);
}

public void setOnCellTouchListener(OnCellTouchListener p) {
    mOnCellTouchListener = p;
}

@Override
protected void onDraw(Canvas canvas) {
    // draw background
    super.onDraw(canvas);
    mWeekTitle.draw(canvas);

    // draw cells
    for(Cell[] week : mCells) {
        for(Cell day : week) {
            day.draw(canvas);           
        }
    }

    // draw today
    if(mDecoration!=null && mToday!=null) {
        mDecoration.draw(canvas);
    }
}



public class GrayCell extends Cell {
    public GrayCell(int dayOfMon, Rect rect, float s) {
        super(dayOfMon, rect, s);
        mPaint.setColor(Color.LTGRAY);
    }           
}

private class RedCell extends Cell {

    public RedCell(int dayOfMon, Rect rect, float s) {
        super(dayOfMon, rect, s);
        mPaint.setColor(0xdddd0000);
    }           

}


}

Cell.java:

  package com.example.calendar_module;

  import android.graphics.Canvas;
  import android.graphics.Paint;
  import android.graphics.Rect;
  import android.graphics.RectF;
  import android.graphics.drawable.Drawable;
  import android.util.Log;

  public class Cell {
private static final String TAG = "Cell";
protected Rect mBound = null;
protected int mDayOfMonth = 1;  // from 1 to 31
protected Paint mPaint = new Paint(Paint.SUBPIXEL_TEXT_FLAG
        |Paint.ANTI_ALIAS_FLAG);
int dx, dy;
protected String mDayString;
private Cell cell ;

public Cell(int dayOfMon, Rect rect, float textSize, boolean bold) {
    mDayOfMonth = dayOfMon;
    mBound = rect;
    mPaint.setTextSize(textSize);
    mPaint.setColor(Color.BLACK);
    if(bold) mPaint.setFakeBoldText(true);

    dx = (int) mPaint.measureText(String.valueOf(mDayOfMonth)) / 2;
    dy = (int) (-mPaint.ascent() + mPaint.descent()) / 2;
}

public Cell(String day,Rect rect,float textSize,boolean bold)
{
    mDayString = day;
    mBound = rect;
    mPaint.setTextSize(textSize);
    mPaint.setColor(Color.BLACK);
    if(bold) mPaint.setFakeBoldText(true);

    dx = (int) mPaint.measureText(String.valueOf(mDayString)) / 2;
    dy = (int) (-mPaint.ascent() + mPaint.descent()) / 2;

}

public Cell(String day , Rect rect , float textSize , int newColor)
{
    mDayString = day;
    mBound = rect;
    mPaint.setTextSize(textSize);
    mPaint.setColor(newColor);


    dx = (int) mPaint.measureText(String.valueOf(mDayString)) / 2;
    dy = (int) (-mPaint.ascent() + mPaint.descent()) / 2;
}

public Cell(int dayOfMon, Rect rect, float textSize) {
    this(dayOfMon, rect, textSize, false);
}
public Cell(String day,Rect rect,float textSize)
{
    this(day,rect,textSize,false);
}

protected void draw(Canvas canvas) {
    canvas.drawText(String.valueOf(mDayOfMonth), mBound.centerX() - dx, mBound.centerY() + dy, mPaint);
}

public int getDayOfMonth() {
    return mDayOfMonth;
}

public boolean hitTest(int x, int y) {
    return mBound.contains(x, y); 
}

public Rect getBound() {
    return mBound;
}

public String toString() {
    return String.valueOf(mDayOfMonth)+"("+mBound.toString()+")";
}




}

CalendarActivity.java

package com.example.calendar_module;

import java.util.GregorianCalendar;

import com.example.calendar_module.CalendarView.OnCellTouchListener;

import android.app.Activity;
import android.content.Intent;
import android.graphics.Color;
import android.graphics.Rect;
import android.os.Bundle;
import android.os.Handler;
import android.text.format.DateUtils;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;

public class CalendarActivity extends Activity{

public static final String MIME_TYPE = "vnd.android.cursor.dir/vnd.example.calendar_module.date";
public static String mClickedDate, mClickedMonth;
CalendarView mView = null;
TextView mHit;
Handler mHandler = new Handler();
private  Button mNextButton;
private Button mPreviousButton;
private TextView mMonthText ;
private int mMonthInt;
private ListView mEventListView;


/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    mView = (CalendarView)findViewById(R.id.calendar);

    mEventListView = (ListView) findViewById(R.id.EventsList);
    mEventListView.setAdapter(new BadgeAdapter(this));

    mView.setOnCellTouchListener(new OnCellTouchListener() {

        @Override
        public void onTouch(Cell cell) {

            TextView mMonthText = (TextView)findViewById(R.id.MonthText);
            mClickedDate = ""+cell.getDayOfMonth();
            mClickedMonth =""+mMonthText.getText();
 //             System.out.println("Clicked date is : "+mClickedDate+" "+mClickedMonth);
 //             startActivity(new Intent(CalendarActivity.this,Event.class));

 //             cell = new Cell(cell.getDayOfMonth(),new Rect(cell.getBound()),Color.MAGENTA);

        }
    });

    mNextButton = (Button) findViewById(R.id.NextMonth);
    mPreviousButton = (Button) findViewById(R.id.PreviousMonth);
    mMonthText = (TextView) findViewById(R.id.MonthText);

    mMonthText.setText(DateUtils.getMonthString(mView.getMonth(), DateUtils.LENGTH_LONG)+", "+mView.getYear());

 //        System.out.println("CurrentMonth is : "+mView.getMonth());

 //        if(getIntent().getAction().equals(Intent.ACTION_PICK))
 //         findViewById(R.id.hint).setVisibility(View.INVISIBLE);
    mNextButton.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            mView.nextMonth();
            mMonthText.setText(DateUtils.getMonthString(mView.getMonth(), DateUtils.LENGTH_LONG)+", "+mView.getYear());

        }
    });

    mPreviousButton.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            // TODO Auto-generated method stub

            mView.previousMonth();
            mMonthText.setText(DateUtils.getMonthString(mView.getMonth(), DateUtils.LENGTH_LONG)+", "+mView.getYear());
        }
    });

    System.out.println("Calendar View Height : "+mView.getHeight());

}



private class RedCell extends Cell {

    public RedCell(Cell cell) {
        super(cell.getDayOfMonth(),new Rect(cell.getBound()), R.dimen.cell_text_size);
        mPaint.setColor(Color.RED);


    }           

  }




}

1 个答案:

答案 0 :(得分:24)

在该视图的onClick()方法中调用mView.invalidate();。这将调用onDraw()(最终),然后运行您的视图的绘图代码。