Android自定义单例AlertDialog详解

 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(); } }