自定义单例 AlertDialog

当android开发处理错误信息时，经常会以Dialog的形式显示错误信息，但是每次都new一个Dialog，很麻烦，也增加程序的开销，所以今天就分享一种自定义单例AlertDialog

public class AlertDialog {    private static AlertDialog alertDialog = null;    private Context context;    private Dialog dialog;    private LinearLayout lLayout_bg;    private TextView txt_title;    private TextView txt_msg;    private Button btn_neg;    private Button btn_pos;    private ImageView img_line;    private Display display;    private boolean showTitle = false;    private boolean showMsg = false;    private boolean showPosBtn = false;    private boolean showNegBtn = false;    public static AlertDialog getInstance(Context context){        if (alertDialog==null){            synchronized (AlertDialog.class) {                if (alertDialog == null) {                    alertDialog = new AlertDialog(context).builder();                }            }        }        return alertDialog;    }    public AlertDialog(Context context) {        this.context = context;        WindowManager windowManager = (WindowManager) context                .getSystemService(Context.WINDOW_SERVICE);        display = windowManager.getDefaultDisplay();    }    public AlertDialog builder() {        // 获取Dialog布局        View view = LayoutInflater.from(context).inflate(R.layout.view_alertdialog, null);        // 获取自定义Dialog布局中的控件        lLayout_bg = (LinearLayout) view.findViewById(R.id.lLayout_bg);        txt_title = (TextView) view.findViewById(R.id.txt_title);        txt_title.setVisibility(View.GONE);        txt_msg = (TextView) view.findViewById(R.id.txt_msg);        txt_msg.setVisibility(View.GONE);        btn_neg = (Button) view.findViewById(R.id.btn_neg);        btn_neg.setVisibility(View.GONE);        btn_pos = (Button) view.findViewById(R.id.btn_pos);        btn_pos.setVisibility(View.GONE);        img_line = (ImageView) view.findViewById(R.id.img_line);        img_line.setVisibility(View.GONE);        // 定义Dialog布局和参数        dialog = new Dialog(context, R.style.AlertDialogStyle);        dialog.setContentView(view);        // 调整dialog背景大小        lLayout_bg.setLayoutParams(new FrameLayout.LayoutParams((int) (display                .getWidth() * 0.85), LayoutParams.WRAP_CONTENT));        return this;    }    public AlertDialog setTitle(String title) {        showTitle = true;        if ("".equals(title)) {            txt_title.setText("标题");        } else {            txt_title.setText(title);        }        return this;    }    public AlertDialog setMsg(String msg) {        showMsg = true;        if ("".equals(msg)) {            txt_msg.setText("内容");        } else {            txt_msg.setText(msg);        }        return this;    }    public AlertDialog setMsg(int rId) {        showMsg = true;        txt_msg.setText(rId);        return this;    }    public AlertDialog setCancelable(boolean cancel) {        dialog.setCancelable(cancel);        return this;    }    public AlertDialog setPositiveButton(String text,            final OnClickListener listener) {        showPosBtn = true;        if ("".equals(text)) {            btn_pos.setText("确定");        } else {            btn_pos.setText(text);        }        btn_pos.setOnClickListener(new OnClickListener() {            @Override            public void onClick(View v) {                if(listener!=null) {                    listener.onClick(v);                }                dialog.dismiss();            }        });        return this;    }    public AlertDialog setNegativeButton(String text,            final OnClickListener listener) {        showNegBtn = true;        if ("".equals(text)) {            btn_neg.setText("取消");        } else {            btn_neg.setText(text);        }        btn_neg.setOnClickListener(new OnClickListener() {            @Override            public void onClick(View v) {                if(listener!=null) {                    listener.onClick(v);                }                dialog.dismiss();            }        });        return this;    }    private void setLayout() {        if (!showTitle && !showMsg) {            txt_title.setText("");            txt_title.setVisibility(View.VISIBLE);        }        if (showTitle) {            txt_title.setVisibility(View.VISIBLE);        }        if (showMsg) {            txt_msg.setVisibility(View.VISIBLE);        }        if (!showPosBtn && !showNegBtn) {            btn_pos.setText("确定");            btn_pos.setVisibility(View.VISIBLE);            btn_pos.setBackgroundResource(R.drawable.alertdialog_single_selector);            btn_pos.setOnClickListener(new OnClickListener() {                @Override                public void onClick(View v) {                    dialog.dismiss();                }            });        }        if (showPosBtn && showNegBtn) {            btn_pos.setVisibility(View.VISIBLE);            btn_pos.setBackgroundResource(R.drawable.alertdialog_right_selector);            btn_neg.setVisibility(View.VISIBLE);            btn_neg.setBackgroundResource(R.drawable.alertdialog_left_selector);            img_line.setVisibility(View.VISIBLE);        }        if (showPosBtn && !showNegBtn) {            btn_pos.setVisibility(View.VISIBLE);            btn_pos.setBackgroundResource(R.drawable.alertdialog_single_selector);        }        if (!showPosBtn && showNegBtn) {            btn_neg.setVisibility(View.VISIBLE);            btn_neg.setBackgroundResource(R.drawable.alertdialog_single_selector);        }    }    public void show() {        setLayout();        dialog.show();    }}

布局文件view_alertdialog.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"    android:id="@+id/lLayout_bg"    android:layout_width="match_parent"    android:layout_height="wrap_content"    android:background="@drawable/alert_bg"    android:orientation="vertical">    <TextView        android:id="@+id/txt_title"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:layout_marginLeft="15dp"        android:layout_marginRight="15dp"        android:layout_marginTop="15dp"        android:gravity="center"        android:text="提示"        android:textColor="@color/black"        android:textSize="18dp" />    <TextView        android:id="@+id/txt_msg"        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:layout_marginLeft="15dp"        android:layout_marginRight="15dp"        android:layout_marginTop="10dp"        android:layout_marginBottom="10dp"        android:gravity="center"        android:text="您确定要退出吗？"        android:textColor="@color/black"        android:textSize="16dp" />    <ImageView        android:layout_width="match_parent"        android:layout_height="0.5dp"        android:layout_marginTop="10dp"        android:background="@color/alertdialog_line" />    <LinearLayout        android:layout_width="match_parent"        android:layout_height="wrap_content"        android:orientation="horizontal">        <Button            android:id="@+id/btn_neg"            android:layout_width="wrap_content"            android:layout_height="43dp"            android:layout_weight="1"            android:background="@drawable/alertdialog_left_selector"            android:gravity="center"            android:text="确定"            android:textColor="@color/bigtextcolor"            android:textSize="16sp" />        <ImageView            android:id="@+id/img_line"            android:layout_width="0.5dp"            android:layout_height="43dp"            android:background="@color/alertdialog_line" />        <Button            android:id="@+id/btn_pos"            android:layout_width="wrap_content"            android:layout_height="43dp"            android:layout_weight="1"            android:background="@drawable/alertdialog_right_selector"            android:gravity="center"            android:text="取消"            android:textColor="@color/themecolor"            android:textSize="16sp" />    </LinearLayout></LinearLayout>

效果显示