使用下面的行,
[fileManager copyItemAtPath:sourcePath toPath:targetPath error:&error];
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我们可以复制文件夹,但如果文件夹已经存在,则会抛出异常"文件存在".为了覆盖单个文件,我们可以通过以下几行来实现:
NSData *myData = [NSData dataWithContentsOfURL:FileURL]; /fetch single file
[myData writeToFile:targetPath atomically:YES];
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但我想复制一个已经存在的文件夹,即覆盖.
编辑:简单的可能性,我可以在复制之前删除这些项目.
请提出更多可能性.
在下面的摘录中,
/*A ClassName with instanceMethod and ClassMethod */
-(void)instanceMethod;
+(void)ClassMethod;
/*To call a instance method in background */
ClassName class1obj = [ClassName alloc] init];
[class1obj performSelectorInBackground:@selector(instanceMethod) withObject:nil];
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同样,如何使用后台调用ClassMethod performSelectorInBackground?
如果可能,请解释!请伙计们携手..
我需要使用蒙版从完整图像剪切并创建蒙版图像.
+
=
我尝试了以下方法:
UIImage *imgMask = [UIImage imageNamed:@"Mask.png"];
UIImage *imgBgImage = [UIImage imageNamed:@"Full.png"];
GPUImageMaskFilter *maskingFilter = [[GPUImageMaskFilter alloc] init];
GPUImagePicture * maskGpuImage = [[GPUImagePicture alloc] initWithImage:imgMask ];
GPUImagePicture *FullGpuImage = [[GPUImagePicture alloc] initWithImage:imgBgImage ];
[maskGpuImage addTarget:maskingFilter];
[maskGpuImage processImage];
[maskingFilter useNextFrameForImageCapture];
[FullGpuImage addTarget:maskingFilter];
[FullGpuImage processImage];
UIImage *OutputImage = [maskingFilter imageFromCurrentFramebuffer];
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但是,我生成的输出图像是: 
请伙计们携起手来.干杯.
还有,感谢BradLarson.
我正在使用包含导航控制器的初始Root-View控制器:

现在我想从uiviewcontroller 1.2.1导航到uiviewcontroller 1.1
所有传统的解决方案,如self.pushview和self.popView功能都不起作用; 他们正在创建包含页面的UITabBarController的另一个实例... Plz家伙携手...任何帮助将不胜感激.........
你们都可能遇到过如下情况:
-(int) fightMath(int one, int two) {
if(one == 0 && two == 0) { result = 0; }
else if(one == 0 && two == 1) { result = 0; }
else if(one == 0 && two == 2) { result = 1; }
else if(one == 0 && two == 3) { result = 2; }
else if(one == 1 && two == 0) { result = 0; }
else if(one == 1 && two == 1) { …Run Code Online (Sandbox Code Playgroud) ios ×5
objective-c ×5
iphone ×4
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