Multiple Titanium progress bars in a table view fo

问题:

I am trying to display the progress of multiple xhr sends in a table view. This is my first shot at a table view (which also is not scrolling for some reason), and I can't figure out the appropriate way to connect the bars to the onsendstream. I appreciate any comments on the rest of my code as well.

my window function

回答1:

I don't claim that multiple simultaneous XHRs are stable, but it is working for me in the simulator. This question was more about the specific UI task whether or not the XHRs are asynchronously queued, but I appreciate any feedback about code quality or best practices. Here is the solution that I arrived at.

// a namespace for the UI code
myApp.ui = {};

// a function for this window
myApp.ui.createCameraWindow = function() {
    var win = Ti.UI.createWindow({
        // I have my own custom header
        title:'',
    });

    var containerView = Ti.UI.createView({
        backgroundColor:'#85AAD7',
    });

    var tableQueue = Ti.UI.createTableView({
        backgroundColor:'#85AAD7',
        separatorColor:'#85AAD7',
        data:photosQueue, // photosQueue is an empty global array
        width:320
    });

    containerView.add(tableQueue);

    // device stores the candidate file on the system and sends data
    Ti.App.addEventListener('photoReady',function(candidate) {
        // here we an add a caption if we please
        var captionView = Ti.UI.createView({
            backgroundColor:'#FFF'
        });

        var candidateIMG = Ti.UI.createImageView({
            // the candidate file was stored with a uniqie identifier called fileStamp
            // don't forget to change resourcesDirectory to tempDirectory for use on the device
            image:Ti.Filesystem.getFile(Ti.Filesystem.resourcesDirectory,candidate.fileStamp + '-thumb320.png'),
            height:367,
            width:320,
            top:0,
            opacity:0.5
        });

        var captionLabel = Ti.UI.createLabel({
            text:'caption',
            color:'#000',
            top:-180,
            textAlign:'center',
            font:{fontSize:50,fontWeight:'bold',fontStyle:'italic',fontFamily:'Cochin'},
            opacity:0.5
        });

        var captionBox = Ti.UI.createTextField({
            height:35,
            width:270,
            textAlign:'center',
            borderStyle:Titanium.UI.INPUT_BORDERSTYLE_ROUNDED
        });

        var submitButton = Ti.UI.createButton({
            title:'Submit',
            color:'#000',
            selectedColor:'#FFF',
            top:220,
            width:130,
            height:35
        });

        captionView.add(candidateIMG);
        captionView.add(captionLabel);
        captionView.add(captionBox);
        captionView.add(submitButton);

        // cover the table view with the temporary caption prompt
        containerView.add(captionView);

        submitButton.addEventListener('click',function(){
            candidate.caption = captionBox.value;
            // start the xhr send from another function
            myApp.remote.createPhoto(candidate);
            // go back to the table view
            containerView.remove(captionView);

            var tempFile = Ti.Filesystem.getFile(Ti.Filesystem.resourcesDirectory,candidate.fileStamp + '-thumb75.png');

            var progressBar = Ti.UI.createProgressBar({
                width:205,
                height:50,
                right:20,
                min:0,
                max:1,
                value:0,
                style:Titanium.UI.iPhone.ProgressBarStyle.PLAIN,
                color:'#FFF'
            });

            var thisRow = Ti.UI.createTableViewRow({
                backgroundColor:'#FFF',
                layout:"vertical",
                height:75,
                fileStamp:candidate.fileStamp
            });

            // apparently the progress bar needs to be inside a view to align correctly
            var nestedView = Ti.UI.createView({
                height:75,
                width:320
            });

            var tinyThumb = Ti.UI.createImageView({
                image:tempFile,
                height:75,
                width:75,
                left:0
            });

            nestedView.add(tinyThumb);
            progressBar.show();
            nestedView.add(progressBar);
            thisRow.add(nestedView);
            photosQueue.push(thisRow);
            tableQueue.setData(photosQueue);
        });
    });

    // the xhr.onsendstream will repeatedly fire this function and send an object containing an id and e.progress
    Ti.App.addEventListener('streamProgress',function(upload) {
        // loop through the global queue
        for (i=0;i<photosQueue.length;i++) {
            // find the the array object that corresponds to the upload object
            if (photosQueue[i].fileStamp == upload.id) {
                // identifiy this object as the tableRow in the UI
                thisRow = photosQueue[i];
                // find its progress bar by knowing the view hierarchy
                var bar = thisRow.children[0].children[1];
                // update the progress bar's value
                bar.value = upload.progress;
                // update the entire tableView with new data
                tableQueue.setData(photosQueue);
            }
        }
    });

    // the xhr.onload will fire this function and send an object containing an id and a status code
    Ti.App.addEventListener('confirmation',function(upload) {
        // loop through the global queue
        for (i=0;i<photosQueue.length;i++) {
            // find the the array object that corresponds to the upload object
            if (photosQueue[i].fileStamp == upload.id) {
                // identifiy this object as the tableRow in the UI
                thisRow = photosQueue[i];
                // if the POST was successful
                if (upload.status == '201') {
                    // then make the entire row pleasing
                    thisRow.backgroundColor = 'green';
                } else {
                    // otherwise make it ugly
                    thisRow.backgroundColor = 'red';
                }
                // identify the full progress bar in the view hierarchy
                var bar = thisRow.children[0].children[1];
                // remove it regardless
                thisRow.children[0].remove(bar);
                // update the entire tableView with new data
                tableQueue.setData(photosQueue);
            }
        }
    });

    win.add(containerView);

    return win;
};