在Phonegap中为iOS压缩图像插件

Question

I am new to ios and building compress image plugin in ios for phonegap.I am not getting how to call the compress image method in my javascript. My code is, Plugin.h file

- (void) cordovaCompressimg:(CDVInvokedUrlCommand *)command;

Plugin.m file

- (void) cordovaCompressimg:(CDVInvokedUrlCommand *)command 
 {
     UIImage *sourceImage ;
     NSString *compimg =[self UIImageToBaseSixtyFour];
CDVPluginResult *pluginResult = [ CDVPluginResult
                             resultWithStatus    : CDVCommandStatus_OK
                             NSData : compimg
                             ];

 [self.commandDelegate sendPluginResult:pluginResult callbackId:command.callbackId];
}


 -(NSData *)UIImageToBaseSixtyFour
  {
    UIImage *sourceImage ;
    NSData *imageData = UIImageJPEGRepresentation(sourceImage, 1.0);

    NSString *base64 = [NSString stringWithFormat:@"%@",[UIImageJPEGRepresentation(sourceImage, 0.95) base64EncodedString]];

    return base64;
}

plugin.js file

window.showimg = function(cimg, callback) {
           cordova.exec(callback, function(err) {
          callback('Nothing to echo.');
          }, "PhonegapPlugin", "cordovaGetCurrentDate", [cimg]);
 };

my calling function in index.html is,

        function showCompressimg() {
                  window.showimg("", function(echoValue) 
                  {
                       alert(echoValue);

                  });
        }

The plugin is getting called but with empty image.The out put comes as null.The source image is not getting passed.Can anybody help me please, Thanks in advance

Answer 1

You are passing the source image correctly, but you are not retrieving the image passed in your argument in objective-c code. Whenever you pass any argument via plugin Javascript, those arguments are stored in CDVInvokedUrlCommand instance command. So you can modify your code like this -

- (void) cordovaCompressimg:(CDVInvokedUrlCommand *)command 
 {
     //Arguments are passed in an Array. Source Image is present at Index 0
     UIImage *sourceImage  = [command argumentAtIndex:0];
     NSString *compimg =[self UIImageToBaseSixtyFour:sourceImage];
CDVPluginResult *pluginResult = [ CDVPluginResult
                             resultWithStatus    : CDVCommandStatus_OK
                             NSData : compimg
                             ];

 [self.commandDelegate sendPluginResult:pluginResult callbackId:command.callbackId];
}


 -(NSData *)UIImageToBaseSixtyFour:(UIImage *)img
  {
    //UIImage *sourceImage ;
    NSData *imageData = UIImageJPEGRepresentation(img, 1.0);

    NSString *base64 = [NSString stringWithFormat:@"%@",[UIImageJPEGRepresentation(img, 0.95) base64EncodedString]];

    return base64;
}