电晕覆盖不显示
Corona Overlay doesn't show
我在场景之间创建加载场景时遇到问题，我得到的解决方案是使用叠加层，我已经尝试了好几天，但由于某种原因我无法让它工作。我有两个场景，一个显示项目列表，另一个显示基于单击哪一行的文本页面。现在的问题是第一个场景，它显示列表，下载要显示的图像，当然这需要一段时间，所以每当我转换到那个屏幕时，应用程序似乎被冻结，而一切都在加载。
我发现它确实进入了覆盖场景，因为我放入其中的打印语句打印出来了，但它什么也没显示，当我删除了隐藏覆盖的代码之后，它似乎仍然挂起，它进入覆盖场景，不显示任何内容然后在最终显示覆盖之前渲染 table 所以不是显示覆盖，而是将所有内容加载到下面，然后隐藏覆盖，它似乎在当前场景中被冻结，加载下面的所有内容，显示覆盖，然后立即隐藏覆盖。
我的三个场景的代码在下面，我现在发布的那个是唯一一个实际工作过一次然后就再也没有工作过的代码，它显示了叠加层，同时一切都按我想要的方式加载但出于某种原因，它那一次之后再也没有工作过。我对此感到非常沮丧，没有论坛给我提供解决方案，我真的很感激一些帮助。谢谢！
ItemListPage.lua
local composer = require ( "composer" )
local widget = require( "widget" )
local json = require( "json" )
-- Load the relevant LuaSocket modules
local http = require( "socket.http" )
local ltn12 = require( "ltn12" )
local scene = composer.newScene()
--NavigationBar elements initiated
--Removed for readability
--image handler
local function networkListener( event )
if ( event.isError ) then
print ( "Network error - download failed" )
end
print ( "event.response.fullPath: ", event.response.fullPath )
print ( "event.response.filename: ", event.response.filename )
print ( "event.response.baseDirectory: ", event.response.baseDirectory )
end
local function onRowRender( event )
-- Get reference to the row group
local row = event.row
local params=event.row.params
local itemRow=3;
-- Cache the row "contentWidth" and "contentHeight" because the row bounds can change as children objects are added
local rowHeight = row.contentHeight
local rowWidth = row.contentWidth
row.rowTitle = display.newText( row, params.topic, 0, 0, nil, 14 )
row.rowTitle:setFillColor( 0 )
row.rowTitle.anchorX = 0
row.rowTitle.x = 0
row.rowTitle.y = (rowHeight/2) * 0.5
--Other elements removed for readabilty (it's all just text objects)
--Download Image
--params referring to items[i]
local imagelink =params.imagelink
-- Create local file for saving data
local path = system.pathForFile( params.imagename, system.TemporaryDirectory )
myFile = io.open( path, "w+b" )
-- Request remote file and save data to local file
http.request{
url = imagelink,
sink = ltn12.sink.file( myFile )
}
row.Image = display.newImageRect(row, params.imagename, system.TemporaryDirectory, 25, 25)
row.Image.x = 20
row.Image.y = (rowHeight/2) * 1.5
row:insert( row.rowTitle )
row:insert( row.Image )
end
local function onRowTouch( event )
local row = event.target
local params=event.target.params
composer.removeScene(composer.getSceneName("current"))
composer.gotoScene( "itempage" , {params=params})
end
function scene:create( event )
local sceneGroup = self.view
end
function scene:show( event )
local sceneGroup = self.view
local phase = event.phase
if phase == "will" then
-- Called when the scene is still off screen and is about to move on screen
--overlay
composer.showOverlay( "loading", { isModal = true })
elseif phase == "did" then
--Table stuff
local scrollBarOptions = {
sheet = scrollBarSheet, -- Reference to the image sheet
topFrame = 1, -- Number of the "top" frame
middleFrame = 2, -- Number of the "middle" frame
bottomFrame = 3 -- Number of the "bottom" frame
}
-- Table
local tableView = widget.newTableView(
{
left = 0,
top = navBar.height,
height = display.contentHeight-navBar.height,
width = display.contentWidth,
onRowRender = onRowRender,
onRowTouch = onRowTouch,
listener = scrollListener
}
)
--json work
local filename = system.pathForFile( "items.json", system.ResourceDirectory )
local decoded, pos, msg = json.decodeFile( filename )
if not decoded then
print( "Decode failed at "..tostring(pos)..": "..tostring(msg) )
else
print( "File successfully decoded!" )
end
local items=decoded.items
-- create a white background to fill screen
local background = display.newRect( display.contentCenterX, display.contentCenterY, display.contentWidth, display.contentHeight )
background:setFillColor( 1 ) -- white
sceneGroup:insert( background )
-- Insert rows
for i = 1, #items do
-- Insert a row into the tableView
print( "Adding a row!" )
tableView:insertRow{
rowHeight = 100,
rowColor = { default={ 0.8, 0.8, 0.8, 0.8 } },
lineColor = { 1, 0, 0 },
params=items[i]
}
end
sceneGroup:insert( tableView )
composer.hideOverlay( "fade", 100 )
end
end
-- other functions and elements unused and removed for readability
loading.lua
local composer = require ( "composer" )
local widget = require( "widget" )
local json = require( "json" )
local scene = composer.newScene()
-- Create the widget
function scene:create( event )
local sceneGroup = self.view
local background = display.newRect( display.contentCenterX, display.contentCenterY, display.contentWidth, display.contentHeight )
background:setFillColor( 1 ) -- white
local text = display.newText( "Loading scene", 0, 0, nil, 14 )
text:setFillColor( 0 )
text.anchorX = display.contentCenterX
text.x = display.contentCenterX
text.y = display.contentCenterY
sceneGroup:insert( background )
sceneGroup:insert( text )
print ( "In loading create")
end
function scene:show( event )
local sceneGroup = self.view
local phase = event.phase
if phase == "will" then
elseif phase == "did" then
print ( "In loading show")
end
end
-- other functions and elements unused and removed for readability
ItemDisplayPage.lua
local composer = require ( "composer" )
local widget = require( "widget" )
local json = require( "json" )
local scene = composer.newScene()
--NavigationBar elements initiated
--This creates the "back button", when clicked it returns to the previous scene, in this case "itemListPage"
--it takes, no parameters
local function handleLeftButton( event )
if ( event.phase == "ended" ) then
composer.removeScene(composer.getSceneName("current"))
composer.gotoScene(composer.getSceneName("previous"))
end
return true
end
--Remaining navbar elements removed for readability
function scene:create( event )
local sceneGroup = self.view
local params=event.params
-- create a white background to fill screen
local background = display.newRect( display.contentCenterX, display.contentCenterY, display.contentWidth, display.contentHeight )
background:setFillColor( 1 ) -- white
--creating header bar
local bar = display.newRect( navBar.height + (headerBarHeight*0.5), display.contentCenterY, display.contentWidth, headerBarHeight )
bar:setFillColor( 1 )
-- create stuff
local title = display.newText(params.topic, 0, 0, nil, 14 )
title:setFillColor( 0 )
title.anchorX = 0
title.x = margin
title.y = ((2*headerBarHeight/2) * 0.5)+navBar.height
local Image = display.newImageRect(params.imagename, system.TemporaryDirectory, 25, 25)
Image.x = 50
Image.y = display.contentCenterY
-- all objects must be added to group (e.g. self.view)
sceneGroup:insert( background )
sceneGroup:insert( title )
sceneGroup:insert( Image)
end
-- other functions and elements unused and removed for readability
我建议您不要使用 scene.show 事件进行加载。
使用timer.performWithDelay加载所有数据：
--in scene:show
elseif phase == "did" then
timer.performWithDelay(0, function()
local scrollBarOptions = {
--put your code here
composer.hideOverlay( "fade", 100 )
end)
您当前的代码未显示覆盖，因为引擎在渲染任何内容之前等待 scene:show 事件。因此，叠加层和图像的渲染发生在所有图像加载完成后。
在我的代码中 timer.performWithDelay 不会阻止 scene:show 执行，因此您会在加载图像之前看到渲染的叠加层
我在场景之间创建加载场景时遇到问题，我得到的解决方案是使用叠加层，我已经尝试了好几天，但由于某种原因我无法让它工作。我有两个场景，一个显示项目列表，另一个显示基于单击哪一行的文本页面。现在的问题是第一个场景，它显示列表，下载要显示的图像，当然这需要一段时间，所以每当我转换到那个屏幕时，应用程序似乎被冻结，而一切都在加载。
我发现它确实进入了覆盖场景，因为我放入其中的打印语句打印出来了，但它什么也没显示，当我删除了隐藏覆盖的代码之后，它似乎仍然挂起，它进入覆盖场景，不显示任何内容然后在最终显示覆盖之前渲染 table 所以不是显示覆盖，而是将所有内容加载到下面，然后隐藏覆盖，它似乎在当前场景中被冻结，加载下面的所有内容，显示覆盖，然后立即隐藏覆盖。
我的三个场景的代码在下面，我现在发布的那个是唯一一个实际工作过一次然后就再也没有工作过的代码，它显示了叠加层，同时一切都按我想要的方式加载但出于某种原因，它那一次之后再也没有工作过。我对此感到非常沮丧，没有论坛给我提供解决方案，我真的很感激一些帮助。谢谢！
ItemListPage.lua
local composer = require ( "composer" )
local widget = require( "widget" )
local json = require( "json" )
-- Load the relevant LuaSocket modules
local http = require( "socket.http" )
local ltn12 = require( "ltn12" )
local scene = composer.newScene()
--NavigationBar elements initiated
--Removed for readability
--image handler
local function networkListener( event )
if ( event.isError ) then
print ( "Network error - download failed" )
end
print ( "event.response.fullPath: ", event.response.fullPath )
print ( "event.response.filename: ", event.response.filename )
print ( "event.response.baseDirectory: ", event.response.baseDirectory )
end
local function onRowRender( event )
-- Get reference to the row group
local row = event.row
local params=event.row.params
local itemRow=3;
-- Cache the row "contentWidth" and "contentHeight" because the row bounds can change as children objects are added
local rowHeight = row.contentHeight
local rowWidth = row.contentWidth
row.rowTitle = display.newText( row, params.topic, 0, 0, nil, 14 )
row.rowTitle:setFillColor( 0 )
row.rowTitle.anchorX = 0
row.rowTitle.x = 0
row.rowTitle.y = (rowHeight/2) * 0.5
--Other elements removed for readabilty (it's all just text objects)
--Download Image
--params referring to items[i]
local imagelink =params.imagelink
-- Create local file for saving data
local path = system.pathForFile( params.imagename, system.TemporaryDirectory )
myFile = io.open( path, "w+b" )
-- Request remote file and save data to local file
http.request{
url = imagelink,
sink = ltn12.sink.file( myFile )
}
row.Image = display.newImageRect(row, params.imagename, system.TemporaryDirectory, 25, 25)
row.Image.x = 20
row.Image.y = (rowHeight/2) * 1.5
row:insert( row.rowTitle )
row:insert( row.Image )
end
local function onRowTouch( event )
local row = event.target
local params=event.target.params
composer.removeScene(composer.getSceneName("current"))
composer.gotoScene( "itempage" , {params=params})
end
function scene:create( event )
local sceneGroup = self.view
end
function scene:show( event )
local sceneGroup = self.view
local phase = event.phase
if phase == "will" then
-- Called when the scene is still off screen and is about to move on screen
--overlay
composer.showOverlay( "loading", { isModal = true })
elseif phase == "did" then
--Table stuff
local scrollBarOptions = {
sheet = scrollBarSheet, -- Reference to the image sheet
topFrame = 1, -- Number of the "top" frame
middleFrame = 2, -- Number of the "middle" frame
bottomFrame = 3 -- Number of the "bottom" frame
}
-- Table
local tableView = widget.newTableView(
{
left = 0,
top = navBar.height,
height = display.contentHeight-navBar.height,
width = display.contentWidth,
onRowRender = onRowRender,
onRowTouch = onRowTouch,
listener = scrollListener
}
)
--json work
local filename = system.pathForFile( "items.json", system.ResourceDirectory )
local decoded, pos, msg = json.decodeFile( filename )
if not decoded then
print( "Decode failed at "..tostring(pos)..": "..tostring(msg) )
else
print( "File successfully decoded!" )
end
local items=decoded.items
-- create a white background to fill screen
local background = display.newRect( display.contentCenterX, display.contentCenterY, display.contentWidth, display.contentHeight )
background:setFillColor( 1 ) -- white
sceneGroup:insert( background )
-- Insert rows
for i = 1, #items do
-- Insert a row into the tableView
print( "Adding a row!" )
tableView:insertRow{
rowHeight = 100,
rowColor = { default={ 0.8, 0.8, 0.8, 0.8 } },
lineColor = { 1, 0, 0 },
params=items[i]
}
end
sceneGroup:insert( tableView )
composer.hideOverlay( "fade", 100 )
end
end
-- other functions and elements unused and removed for readability
loading.lua
local composer = require ( "composer" )
local widget = require( "widget" )
local json = require( "json" )
local scene = composer.newScene()
-- Create the widget
function scene:create( event )
local sceneGroup = self.view
local background = display.newRect( display.contentCenterX, display.contentCenterY, display.contentWidth, display.contentHeight )
background:setFillColor( 1 ) -- white
local text = display.newText( "Loading scene", 0, 0, nil, 14 )
text:setFillColor( 0 )
text.anchorX = display.contentCenterX
text.x = display.contentCenterX
text.y = display.contentCenterY
sceneGroup:insert( background )
sceneGroup:insert( text )
print ( "In loading create")
end
function scene:show( event )
local sceneGroup = self.view
local phase = event.phase
if phase == "will" then
elseif phase == "did" then
print ( "In loading show")
end
end
-- other functions and elements unused and removed for readability
ItemDisplayPage.lua
local composer = require ( "composer" )
local widget = require( "widget" )
local json = require( "json" )
local scene = composer.newScene()
--NavigationBar elements initiated
--This creates the "back button", when clicked it returns to the previous scene, in this case "itemListPage"
--it takes, no parameters
local function handleLeftButton( event )
if ( event.phase == "ended" ) then
composer.removeScene(composer.getSceneName("current"))
composer.gotoScene(composer.getSceneName("previous"))
end
return true
end
--Remaining navbar elements removed for readability
function scene:create( event )
local sceneGroup = self.view
local params=event.params
-- create a white background to fill screen
local background = display.newRect( display.contentCenterX, display.contentCenterY, display.contentWidth, display.contentHeight )
background:setFillColor( 1 ) -- white
--creating header bar
local bar = display.newRect( navBar.height + (headerBarHeight*0.5), display.contentCenterY, display.contentWidth, headerBarHeight )
bar:setFillColor( 1 )
-- create stuff
local title = display.newText(params.topic, 0, 0, nil, 14 )
title:setFillColor( 0 )
title.anchorX = 0
title.x = margin
title.y = ((2*headerBarHeight/2) * 0.5)+navBar.height
local Image = display.newImageRect(params.imagename, system.TemporaryDirectory, 25, 25)
Image.x = 50
Image.y = display.contentCenterY
-- all objects must be added to group (e.g. self.view)
sceneGroup:insert( background )
sceneGroup:insert( title )
sceneGroup:insert( Image)
end
-- other functions and elements unused and removed for readability
我建议您不要使用 scene.show 事件进行加载。
使用timer.performWithDelay加载所有数据：
--in scene:show
elseif phase == "did" then
timer.performWithDelay(0, function()
local scrollBarOptions = {
--put your code here
composer.hideOverlay( "fade", 100 )
end)
您当前的代码未显示覆盖，因为引擎在渲染任何内容之前等待 scene:show 事件。因此，叠加层和图像的渲染发生在所有图像加载完成后。
在我的代码中 timer.performWithDelay 不会阻止 scene:show 执行，因此您会在加载图像之前看到渲染的叠加层