main.pas

《深入Delphi的多媒体编程》实例源代码

unit main;

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs,
  FileCtrl, StdCtrls, ExtCtrls, Buttons,Jpeg, MPlayer;

type
  TMainForm = class(TForm)
    DriveComboBox1: TDriveComboBox;
    FilterComboBox1: TFilterComboBox;
    DirectoryListBox1: TDirectoryListBox;
    FileListBox1: TFileListBox;
    Bevel1: TBevel;
    Panel1: TPanel;
    BigViewBitBtn: TBitBtn;
    CloseBitBtn: TBitBtn;
    MediaPlayer1: TMediaPlayer;
    procedure CloseBitBtnClick(Sender: TObject);
    procedure BigViewBitBtnClick(Sender: TObject);
    procedure FileListBox1Click(Sender: TObject);
  private
    { Private declarations }
    FileExt:String[4];//存放文件扩展名
  public
    { Public declarations }
    AviPictureWidth,AviPictureHeight:Integer;//存放动画的宽高
  end;

var
  MainForm: TMainForm;

implementation

uses Bigpas;

{$R *.DFM}
procedure TMainForm.FileListBox1Click(Sender: TObject);//选择文件播放
begin
 BigViewBitBtn.Enabled:=False;
 FileExt:=AnsiLowerCase(ExtractFileExt(FileListBox1.FileName));//文件扩展名小写化
 if FileExt='.wav' then//是声音
  begin
    Panel1.Caption:='播放声音';
    MediaPlayer1.Close;
    MediaPlayer1.FileName:=FileListBox1.FileName;
    MediaPlayer1.Open;
    MediaPlayer1.Play;
  end
 else
  if FileExt='.avi' then//是动画
   begin
     BigViewBitBtn.Enabled:=True;
    with MediaPlayer1 do
     begin
      Close;
      display:=Panel1;//播放窗口
      FileName:=FileListBox1.FileName;
      Panel1.Caption:='';
      Open;
      Rewind;
      AviPictureWidth:=DisplayRect.Right;//保存动画的宽高
      AviPictureHeight:=DisplayRect.Bottom;
      Play;
     end;
   end
  else
    if FileExt='.mid' then//是音乐
     begin
      Panel1.Caption:='播放音乐';
      MediaPlayer1.Close;
      MediaPlayer1.FileName:=FileListBox1.FileName;
      MediaPlayer1.Open;
      MediaPlayer1.Play;
     end;
end;

procedure TMainForm.BigViewBitBtnClick(Sender: TObject);//对中播放动画处理
begin
 if (FileListBox1.FileName<>'') and (FileExt='.avi') then//文件存在
  begin
   with BigForm do
    begin
     Panel1.Height:=AviPictureHeight;
     Panel1.Width:=AviPictureWidth;
     Panel1.Color:=clBlack;
     Panel1.BevelOuter:=bvNone;
     if (AviPictureHeight>BigForm.ClientHeight) and (AviPictureWidth>BigForm.ClientWidth) then
       begin//图形宽高大于窗体时
        BigForm.Panel1.Top:=0;
        BigForm.Panel1.Left:=0;
        ShowMessage('1');
       end
      else
       if AviPictureHeight>BigForm.ClientHeight then
        begin//图形高大于窗体高时
         BigForm.Panel1.Top:=0;
         BigForm.Panel1.Left:=(BigForm.ClientWidth-AviPictureWidth) div 2;
         ShowMessage('2');
        end
       else
        if AviPictureWidth>BigForm.ClientWidth then
         begin//图形宽大于窗体宽时
          BigForm.Panel1.Top:=(BigForm.ClientHeight-AviPictureHeight) div 2;
          BigForm.Panel1.Left:=0;
          ShowMessage('3');
         end
        else
         begin//图形宽高小于等到于窗体宽高时
          BigForm.Panel1.Top:=(BigForm.ClientHeight-AviPictureHeight) div 2;
          BigForm.Panel1.Left:=(BigForm.ClientWidth-AviPictureWidth) div 2;
         end;
      Color:=clBlack;//设置窗体颜色为黑色
      Caption:=FileListBox1.FileName;//显示文件名
      with MediaPlayer1 do//播放动画
       begin
        Close;
        Display:=BigForm.Panel1;
        FileName:=FileListBox1.FileName;
        Open;
        Play;
       end;
      Show;//显示大图
    end;  
  end;
end;

procedure TMainForm.CloseBitBtnClick(Sender: TObject);
begin
 MediaPlayer1.Close;
 Close;
end;

end.