Android实现未读消息小红点显示实例

目录

• 代码实现
• 小红点实现
• 总结

import android.graphics.canvas;
import android.graphics.colorfilter;
import android.graphics.paint;
import android.graphics.pixelformat;
import android.graphics.drawable.drawable;
import android.graphics.drawable.shapedrawable;

import androidx.annotation.intrange;
import androidx.annotation.nonnull;
import androidx.annotation.nullable;


public class circledrawable extends shapedrawable {
    private paint mpaint;
    private int mradio;

    public circledrawable(int radio, int paincolor) {
        mpaint = new paint();
        mpaint.setantialias(true);
        mpaint.setcolor(paincolor);
        mradio = radio;
    }

    @override
    public void draw(@nonnull canvas canvas) {
        canvas.drawcircle(mradio, mradio, mradio, mpaint);
    }

    @override
    public void setalpha(@intrange(from = 0, to = 255) int i) {
        mpaint.setalpha(i);
    }

    @override
    public void setcolorfilter(@nullable colorfilter colorfilter) {
        mpaint.setcolorfilter(colorfilter);
    }

    @override
    public int getopacity() {
        return pixelformat.translucent;
    }

    /***
     * drawable实际宽高，圆形关键
     *
     * @return
     */
    @override
    public int getintrinsicwidth() {
        return mradio * 2;
    }

    @override
    public int getintrinsicheight() {
        return mradio * 2;
    }
}

import android.content.context;
import android.graphics.canvas;
import android.graphics.color;
import android.graphics.rect;
import android.graphics.drawable.colordrawable;
import android.graphics.drawable.shapedrawable;
import android.graphics.drawable.shapes.ovalshape;
import android.graphics.drawable.shapes.roundrectshape;
import android.util.attributeset;
import android.util.printer;
import android.view.gravity;
import android.view.view;
import android.view.viewgroup;
import android.widget.framelayout;
import android.widget.textview;

import androidx.annotation.nullable;

import com.primer.common.constant.gravitydirection;
import com.primer.common.mvp.logininterface;
import com.primer.common.util.loghelper;
import com.primer.common.util.uihelper;
import com.primer.common.view.drawable.circledrawable;

public class badgeview extends textview {

    private final int default_badge_radio = 5;
    private final int default_text_size = 5;
    private final int default_text_color = color.white;
    private final int default_badge_color = color.red;
    private final int default_badge_gravity = gravitydirection.direct_top_left;

    private string mtext;
    private int mbadgecolor = default_badge_color;
    private int mtextcolor = default_text_color;
    private int mtextsize = default_text_size;
    private int mbadgeradio = default_badge_radio;
    private int mbadgegravity = default_badge_gravity;

    private framelayout mfragmentlayout;
    private viewgroup mtargetviewgroup;
    private view mtarget;
    private context mcontext;

    public badgeview(context context) {
        super(context);
        init(context);
    }

    public badgeview(context context, @nullable attributeset attrs) {
        super(context, attrs);
        init(context);
    }

    public badgeview(context context, @nullable attributeset attrs, int defstyleattr) {
        super(context, attrs, defstyleattr);
        init(context);
    }

    public badgeview(context context, @nullable attributeset attrs, int defstyleattr, int defstyleres) {
        super(context, attrs, defstyleattr, defstyleres);
        init(context);
    }

    private void init(context context) {
        mfragmentlayout = new framelayout(context);
        mfragmentlayout.setlayoutparams(new framelayout.layoutparams(
                viewgroup.layoutparams.match_parent, viewgroup.layoutparams.match_parent));
        mcontext = context;
    }

    /***
     *
     * @param content
     * @param target
     * @param textcolor
     * @param textsize
     * @param badgecolor
     * @param badgeradio
     */
    public void showbadgeview(string content, view target, int textcolor, int textsize, int badgecolor, int badgeradio) {
        if (target == null) {
            throw new illegalargumentexception("target view must not be null");
        }

        mtarget = target;
        mtargetviewgroup = (viewgroup) target.getparent();
        mtargetviewgroup.removeview(target);
        mtargetviewgroup.addview(mfragmentlayout, target.getlayoutparams());

        settextcolor(mtextcolor);
        settextsize(mtextsize);
        setgravity(gravity.center);
        if (content != null && content.length() <= 3) {
            settext(content);
        }

          //文字和半径之间的适配
        if (content != null) {
            rect rect = new rect();
            this.getpaint().gettextbounds(content, 0, content.length(), rect);
            if (content.length() <= 3 && rect.width() >= mbadgeradio) {
                mbadgeradio = (uihelper.px2dip(mcontext, rect.width()) / 2) + 1;
            }
        }

        setbackgrounddrawable(getshapedrawable());
        mfragmentlayout.addview(target);
        mfragmentlayout.addview(this);
        mtargetviewgroup.invalidate();
    }


    private shapedrawable getshapedrawable() {
        int radio = uihelper.dip2px(mcontext, mbadgeradio);
        circledrawable drawable = new circledrawable(radio, mbadgecolor);
        return drawable;
    }

    /***
     *
     * @param content
     * @param target
     */
    public void showbadgeview(string content, view target) {
        showbadgeview(content, target,
                default_text_color,
                default_text_size,
                default_badge_color,
                default_badge_radio);
    }

    public void showbadgeview(view target) {
        showbadgeview(null, target,
                default_text_color,
                default_text_size,
                default_badge_color,
                default_badge_radio);
    }

    @override
    protected void onmeasure(int widthmeasurespec, int heightmeasurespec) {
        super.onmeasure(widthmeasurespec, heightmeasurespec);
    }

    @override
    protected void ondraw(canvas canvas) {
        super.ondraw(canvas);
    }

    @override
    protected void onlayout(boolean changed, int left, int top, int right, int bottom) {
        super.onlayout(changed, left, top, right, bottom);
    }
}

    private badgeview mreadbadgeview;
    private textview mread;

	mreadbadgeview = new badgeview(getactivity());
    mreadbadgeview.showbadgeview("+99", mread);